The demure Jenny Packham dress donned by Duchess of Cambridge as she left hospital was surprisingly Diana-esque

Her absolute normality, her girl-next-door-ness, is a key element of the Duchess of Cambridge's popularity. And on these, her own terms, she got the Lindo Steps Look absolutely right. Her cornflower-blue polka dot dress was a safe choice, being demure and pretty and by a British designer, Jenny Packham. The colour was clunkily literal. (One assumes there is a rose pink version hanging in a cupboard somewhere.) Kate loves a fancy frock when the occasion demands it, but 24 hours after having a baby is absolutely not the moment to be experimenting with directional looks. That would be weird, and weird is one thing that Kate is most certainly not.

The one surprising element was how Diana-esque the look was. The image of Diana in polka dots on the same steps in 1982 has been much revisited in recent days, and there was a clear echo of that dress here. Whether the echo was a conscious one, or made unconsciously via the sleep-and hormone-muddled haze of new motherhood, we can only speculate. Like Diana, Kate has the glamour-hair of her generation.

Where Diana had her frosted and flicked fringe, Kate has her thick Disney waves. Good hair imparts glamour whatever you wear. As for the baby Prince, the neutral shawl gave little away. The scoop on the first royal babygro is still out there for the taking.

Jess Cartner-Morley chooses some vamp-it-up shades for your fashion wardrobe

'Walk into a party wearing OTT sunglasses, and half the people there will write you off before you've opened your mouth. You've typecast yourself as a baddie, just like that'

Should you ever want to character-assassinate yourself, you can do this with the help of one simple accessory. All you need to look like a tosser is a monster pair of sunglasses. Walk into a party wearing an OTT pair of shades, and half the people there will write you off before you've opened your mouth. No need to go to the trouble of formulating and voicing offensive opinions: you've typecast yourself as a baddie, just like that.

Today, however, I will attempt to defend the indefensible. My goal is nothing less than the rehabilitation of power sunglasses – the unnecessarily large, deliberately expensive kind.

The benefit of big sunglasses is that they are a no-effort way to turn up the volume on your summer wardrobe. A serious pair of shades packs a lot of attitude, and this can be turned to your advantage if you want to make your summer wardrobe more punchy. Much easier, in hot weather, than adding high heels, and with just as much added glamour. And a pair of shades isn't just a low-maintenance addition – it's positively time-saving, because you can skip eye makeup.

This summer's most on-trend sunglasses are boxy, squared-off shades that seem to channel 3D specs. There is nothing particularly face-flattering about them, but they are unmistakably Fashion. Aviator styles, by contrast, were an off-beat vintage classic two years ago, but, having been discovered for their cheekbone-enhancing properties, have become slightly Wag. Wear square shades to edge up a flirty dress, or aviators to make the utilitarian more alluring.

The classic vamp-it-up shades are the big, curvy, movie-star kind; the "who does she think she is?" sort. If you are trying to look approachable and down to earth, these won't do you any favours. But if you're trying to ratchet your look from normal to reasonably glamorous, there is no faster way. A pair of these transforms a subtle, demure look into a statement of Grace Kelly intent. Key word here: intent. To harness the impact of sunglasses without turning the world against you, remember you are not, actually, Grace Kelly, but just wearing large sunglasses. That way, you get to look like the star, not the baddie.

• Jess wears dress, £1,055, by Rochas, from matchesfashion.com. Sunglasses, £320, by Linda Farrow, from brownsfashion.com. Sandals, £45, riverisland.com.

Hair and makeup: Tonee Roberio using Mac Cosmetics.

How well do you know your Instagram filters? Is your sundress channelling the right celebrity? Take our style quiz and discover just how hip your summer really is

Jess Cartner-Morley picks out some statement skirts to wear with plain T-shirts

'In 2013, there's a new twist on the smart-with-casual equation: it's been turned upside down'

The whole point of fashion is to look up to date rather than old-fashioned. Fashionable is just another word for modern, really. Fashion deliberately makes modernity tricky to decipher by including a few random elements – leather fringing, or 1930s Shanghai, or ankle-strap shoes – that are there to make the whole process more exclusive. A bit like modern passwords making you include a numeral and a capital letter. It keeps out the hoi polloi.

One of the key fashion passwords, if you will, of the past few years has been to mix up the formality levels of the top and bottom of your outfit. So instead of wearing a tailored jacket with matching trousers, you wear a blazer with jeans, which signals smart without looking square. I mean, duh. But in 2013 there's a new twist on this smart-with-casual equation: it has been turned upside down. Whereas previously the formula centred around a fancy top half and a dressed-down bottom half ( for a festival look, that might be a pretty Isabel Marant-esque top with cut-off shorts), the newest take on this is a dressed-down top half with a sharper bottom half.

The trend started earlier this year, with the emergence of the sweatshirt-plus-pencil-skirt as A Look. This is the 2013 version of the silk blouse with jeans: a classic smart-casual combination, with the ingredients upended. As the year has gone on, other trends have fallen by the wayside after their six-week stint in high street windows, but this one has gathered strength. A statement skirt with a casual top is a simple, modern look. For summer, it can be a Dior-esque full skirt with a good-quality cotton T-shirt; for autumn, it might well be a simple polo-neck sweater with, say, a kilt. (Yes, a kilt. More on this another day.)

To keep up, we need to rethink the quick-hit shopping trip. Most of us, when looking for a fast fashion update, instinctively look for a dress, or a top we can wear with jeans or a jacket. But this is a route to looking old-fashioned, not fashionable. Instead, zero in on a statement skirt. The world keeps turning, and right now it's upside down.

• Jess wears prom skirt, £48, topshop.com. T-shirt, £16, americanapparel.net. Shoes, £65, office.co.uk.

Hair and makeup: Tonee Roberio using Mac Cosmetics.

'Keep an eye out for camouflage in metallic fabrics and plaid mixed in with cashmere'

Let's have a quick game of word association. I say "grunge". You want to say "Courtney Love", don't you? And I'm willing to guess that if you were 16 or thereabouts when Nirvana were at their peak, then the thought of silky nighties, leopard print and army boots might make you smile with nostalgia, but it probably doesn't inspire you to go shopping. Well, whaddayaknow, grunge is back. The difference being that this time it has been given a polish, and so here I am wearing check, camo and tailored trousers in an attempt to give you "grown-up grunge".

To be honest, elements of the look have been bubbling under for a while. Those posh teenagers who knock around backstage areas at festivals with Prince Harry and Cara "big brows" Delevingne have been wearing plaid, beanies and big boots all summer. Meanwhile Hedi Slimane, the rebel currently in charge of the Saint Laurent brand, has taken the label down a grunge side road (albeit his army boots cost about 20 times as much as the ones you might remember from your local army and navy surplus store).

Don't be all faux shocked. That's catwalk fashion for you, and it does highlight the fact that right now grunge is more of a look than a lifestyle. Which is why the high street will be selling a version over the coming months. Take Whistles, past masters of packaging trends into real, well-made clothes. They have taken elements of grunge, such as camouflage, and re-imagined them in slick parkas and coats that grown-up women would wear on their commute rather than with matted hair at a gig.

What makes grunge grown-up this time is the mix of fabrics plus the way you wear it. So keep an eye out for camouflage in metallic fabrics and plaid mixed with cashmere, and wear such stuff with tailoring. A classic pair of navy ankle-length trousers or a sharp pencil skirt: that's the right amount of contrast to make the trend feel modern.

Memories of Famous Army Stores still too vivid to try this trend? Not much that I or the high street can do about that, I'm afraid. Nevermind.

• Imogen wears shirt, £86, by Ganni from my-wardrobe.com. Jumper, £325, by MSGM from brownsfashion.com. Trousers, £35.99, and heels, £29.99, both zara.com.

Styling: Melanie Wilkinson. Hair and makeup: Sharon Ive at Carol Hayes Management.

Jess Cartner-Morley is away.

From the painted talons of music maven Rihanna to sporting star Rebecca Adlington − nails are now big business

The meaning of the manicure has been transformed in the last few years. Until recently, painted nails were a symbol of classic, grown-up elegance. Traditional shades with timeless names – pillarbox red, or ballet-slipper pink – dominated the market. But the boom in nail art and the trend for eyebrow-raising colours – like steel grey, neon tangerine and moss green – have turned the rules upside down. Nails have never been so high profile in fashion and in popular culture and a new generation of young women are using nail polish to express their individuality, their fashion savvy, creativity and even their humour.

Nail art – the painstaking business of painting and gluing designs and tiny jewels onto nails often lengthened with extensions to create a larger canvas – has its roots in small local salons, but has rapidly become big business and a favourite of female celebrities from the worlds of music, sport and fashion. Last year, the American singer Katy Perry attended the MTV awards with a custom-painted manicure in which the names of each single from her most recent album were represented on different nails. Rihanna has been photographed with hundreds of different eye-catching manicures, from Acid House smiley faces to sharpened metallic talons. Fresh from the manicurist, many Instagram their new looks around the world.

At the 2012 Olympics, patriotic nail art was the trend to sweep the park, with Rebecca Adlington's union flag nails competing for attention with US swimmer Missy Franklin's stars and stripes. The Olympics became a showcase for the wholesome, family-friendly face of nail art – a stark contrast with 2010, when the troubled actress Lindsay Lohan famously painted "fuck U" on the fingernail of her middle finger for a court appearance.

That the nail art phenomenon took off at the Olympics reflects the fact that London has long been the engine room of the trend. The young entrepreneur Sharmadean Reid, a pioneer when she founded WAH nails in Dalston in 2008, has been key in pushing the boundaries of painted nails, as has Vogue-endorsed nail technician Sophy Robson− who has been responsible for some eye-catching magazine manicures.

Beauty bloggers are currently tipping the half-moon manicure – an updated version of the traditional French, in which the half-moon at the base is painted a contrasting colour to the rest of the nail, as the coming trend. Lake Bell, the writer, director and star of hotly tipped new comedy In A World, sported the look in navy and gold at the Sundance Film Festival this year.

The T-blouse combines the comfort of a T-shirt with the sense of occasion of a blouse. Jess Cartner-Morley chooses a selection for your wardrobe

Controversy and protest overshadow the glamour at the New York City shows

Just two days into New York fashion week, the new mood for the catwalk season is already emerging – and it's not pretty.

Thorny issues of racism on the catwalk, of the impact of fashion on our relationship with food, of the decreasing relevance of the traditional catwalk show in the digital age, and of the bloated size of the fashion industry are the topics engrossing the front row.

In an industry known for champagne-drenched parties and sequinned celebrities – and where a crisis usually refers to a snapped stiletto – this newly gritty tone is an unexpected new trend. Glamour and gossip are out. Controversy, protest and soul-searching are in.

Discontent has been rumbling at New York fashion week since 2010, when the official catwalks were relocated from the more intimate Bryant Park space to the Lincoln Centre. New York designers, long sensitive to criticism that their city is overly commercial and lacks the creative spark of fashion in Paris or London, have complained that the venue has a "trade show" feel which exacerbates the problem. The event may move as early as next year – but with no new venue lined up, a mood of insecurity has taken hold.

Diane von Fürstenberg, one of the city's star designers and president of its fashion council, the CFDA, has openly speculated that physical fashion shows may be made extinct by digital substitutes within the next few years. Oscar de la Renta, one of the most revered American designers, stoked the fire last week when he told Womenswear Daily that he was cutting his invitation list from 632 to 350 this season in an attempt to avoid "huge crowds of people with no connections to the clothes".

Into this fraught atmosphere, the emotive issue of racism on the catwalk is being brought into focus by Bethann Hardison, a former model and agent who has waged a longstanding campaign for more diversity on the catwalk.

During this week's shows she plans to use social media to "name and shame" the designers who use only white models. The model Iman, lending her support to Hardison, told the New York Times that "it feels to me like the times need a real hard line drawn like in the 1960s, by saying if you don't use black models, then we boycott".

Calvin Klein, a label once known for racially diverse catwalk casting but which has become more homogeneously white in recent seasons, is one of the shows that will come under scrutiny this week.

Meanwhile, the influential French fashion blogger Garance Doré has revived the longstanding debate about how the industry's worship of clothes showcased on very thin models affects our eating habits. After commenters reacted negatively to a video in which Doré and her friends referred to not eating dessert at lunch because of the need to fit into their fashion week outfits, Doré responded with a post attacking the double standards and dishonesty rife in the media, where ultra-slender actresses maintain a pretence of eating cheeseburgers.

"I'm trying to talk about femininity, exactly how it is in life … not that weird distorted version that I see in certain media outlets … What I like to show are the real women around me who aren't trying to make others believe they live in some magic world where they only eat burgers, never work out, and by the way also wear two million dollar outfits as if they were falling from the skies."

Hardison's social media campaign and Doré's use of her blog to weigh into debate are symptomatic of how the internet has energised and expanded fashion.

But faultlines are developing within a once tight-knit world, as the huge growth in numbers of fashion bloggers has brought a backlash among traditionalists who feel their industry is being overtaken by amateurs.

Suzy Menkes, who has been fashion editor of the International Herald Tribune for 25 years, this year prompted controversy with an article lamenting the advent of "mob rule" in the industry, and drew a distinction between the professionals and the "peacocks" who create a "streetstyle" circus around every show.

Ahead of London fashion week, which begins next Friday, the British Fashion Council this week tackled this issue with the announcement of more stringent guidelines on the accreditation of bloggers. The move comes in response to a 25% rise in ticket applications from bloggers in each of the past two years. Only those bloggers who have a wide reach and evidence that they support the work of British designers will be accredited in future, a move which the established blogger Susie Lau of Style Bubble welcomed as helping "establish blogging as a legitimate media channel".

She has convictions for assault, a ban from British Airways and called her summons to Charles Taylor's war crimes tribunal 'a big inconvenience'. Now the original super is turning mentor for a TV modelling competition. Is there a softer side to Naomi Campbell?

She's late. Of course she's late. You don't get to be a one-name-only celebrity by deviating from your brand, and Naomi Campbell is always late. It's as much a part of her brand as being absurdly beautiful, and the real-life Campbell does not disappoint on either count. As the hours tick away and a 10-strong shoot crew flick through magazines and direct hopeful glances at the door every time it swings open, I am reminded of the words of Miss Jean Brodie, when summoned to a meeting at 4.15pm: "Four fifteen. Not four, not 4.30, but 4.15. Hmm. She thinks to intimidate me by the use of quarter-hours?"

Today, Campbell intimidates to the tune of two hours, 51 minutes. The door swings open, and suddenly there she is: short, black Azzedine Alaia sundress and Alaia gladiator sandals, diva shades, phone clamped to one ear. The lighting assistants watch her while pretending to do something with gaffer tape; the catering team take their time gathering the coffee pots; the work experience girls simply try not to gawp. She struts across the huge studio, hips swinging in that unmistakable one-two motion that Vogue once described as her "magic runway boom-boom", to the relative quiet of the makeup room. Here she will be styled for our Hitchcock heroines shoot.

When she finishes her phone call, I introduce myself. "Hello how are you nice to meet you," she replies, her monotone dripping with ennui. The tone is that of a cocktail party hostess greeting an uninvited guest whom she would quite like to throw out but has decided to tolerate.

She is all cheekbones and plump lips; high, round bottom and long, lean thigh muscle. It's not just an awesome body for 43, it's an awesome body full stop. Before she has even sat down in the makeup chair, she looks every inch the supermodel.

In fact, Campbell outgrew the supermodel label a long time ago. This is a woman who was teenage roommates with Christy Turlington and is Nelson Mandela's honorary granddaughter, who has appeared in music videos for Bob Marley and George Michael, and whose ex-boyfriends include Robert De Niro and Mike Tyson. Tyson, asked to describe Campbell when they were going out, famously said of her, "She's scared of nothing."

Between 1998 and 2008, Campbell was as much a fixture of the tabloids as she was of the glossies. She admitted assaulting a personal assistant, Georgina Galanis, with a mobile phone; throwing a gem-encrusted BlackBerry at a housekeeper, Ana Scolavino; and assaulting two police officers at Heathrow, in a row over lost luggage that earned her a five-year ban from British Airways. When sentenced to community service and sweeping the streets of New York, Campbell kept a diary for W magazine that was accompanied by photographs by Steven Klein of her reporting for duty wearing a floor-length, silver-sequinned Dolce & Gabbana gown. The message of that image – you can bring me down to earth, but you will never humble me – was repeated in 2010, when she gave her infamous "blood diamonds" testimony at the trial of former African warlord Charles Taylor, dressed in the queenly beehive and sharp lemon pastels of a southern belle, and described her time in the witness box as "a big inconvenience".

Now, a full quarter-century after her first Vogue cover, comes a new chapter in the Campbell story. Not for Campbell the redemption tale, the ceremonial eating of humble pie. Instead, she has used the take-no-prisoners bossiness that for years served as a distraction from her day job to develop a second career.

She is now a presenter and executive producer on The Face, a search-for-a-star TV modelling show in which three mentors – Campbell, Erin O'Connor and Caroline Winburg – pit their talent-spotting, career-nurturing and strategising skills against each other in a bid to back the winner in a race for a Max Factor modelling contract. In other words, the Next Top Model formula has been spiced up with a little of the emotional, team-building spirit of The Voice and a lot of the tough-love, in-it-to-win-it attitude of The Apprentice. Campbell gets to play the Alan Sugar role of lovable villain.

Certainly she likes to run the show. The shoot takes a long time, held up for a while as Campbell has business calls to make, and then because she is less than happy with the aesthetic of the pictures, and has to call in some of her personal team. Eventually she and I sit down, perched at the makeup table, so that Campbell can be restyled for her evening engagements while we talk. I switch on the recording app on my phone. "I've got a better one," she says immediately, pulls two iPhones from her handbag and swipes impatiently across the screens in search of the app. She is being helpful, no doubt about that, but there is an unconscious note of power play – not to mention the sweet irony of my having provoked her into pulling not one but two phones out of her bag within seconds of us sitting down.

I ask her why she said yes to The Face, having turned down TV before, and she says: "I started talking to Liz Murdoch [whose company Shine produces The Face] around 10 years ago and the conversation evolved, and when this came along it felt like it was finally the right thing. I like that I am a mentor on this show, not a judge. I don't want a young woman to feel like her dreams have been blown because of me – I want to help her reach her dreams. I have an opportunity to share what I've learned over 27 years, and that's a powerful thing."

If The Face shows a warmer side of Campbell no one is pretending she has gone soft. She describes herself as a "mother hen" to her "girls", but her idea of nurturing is, in her words, "tough love. I'm straight up, I'm honest. When my girls do something great, I praise them and pamper them. And when they do something wrong, I'm gonna tell them. I'm not gonna sugarcoat it, because they're not going to get it sugarcoated in the real world. Everyone makes mistakes but you have to learn from those mistakes if you want to get on."

No one in the industry who knows Campbell will tell you she is a pussycat or a pushover, but many speak highly of her loyalty, her commitment to causes she believes in. The refrain most often repeated about her by people who know her well is that she is a one-off, "there's no one like her". During our time together, the personality she projects is one of old-school, aloof unknowability. Fun and warmth are kept well guarded behind the velvet ropes. But when she chooses to turn it on, she has immense personal magnetism, which has enabled her to forge close and lasting relationships with designers, business moguls and other models – relationships that have done much to shield her from the quicksand into which many models' careers disappear. Her friend Donatella Versace once said of Campbell: "They say she is spoiled and annoying. But she's not. She's very determined and very generous, and these are two qualities that nobody ever talks about."

In the summer of 1985, Campbell was a 15-year-old schoolgirl from Streatham, south London. While window-shopping in Covent Garden, she was spotted by a model agent; before her 16th birthday she was on the cover of British Elle. "I didn't know how to model," she says. "I wasn't spending my pocket money on buying magazines, so I didn't know how models were supposed to look. So I just kind of made it up. Instinctively, I used my dance background to help me, jumping in the air, and the photographers liked it."

A year later, in Paris, she found her own mentor. "I was shooting for French Elle, and for some reason I took my passport and money to work and it kind of disappeared. And a model who was there that day was going to dinner with Azzedine [Alaia] and she took me along, with my mother. So we went, and I couldn't speak French, but my mother could and he [Alaia] spoke to her and said, I'm going to take care of your daughter; she's going to stay with me. He's been that way ever since. I call him Papa."

"As a model," she says, she "learned from the greats. Yves Saint Laurent was very supportive of me. He was very quiet, kind of twinkly-eyed. He didn't talk very much and we were not really supposed to speak to him, but I did. Gianni Versace was incredibly supportive of the models he worked with. When he would get an award or be honoured in some way, he would want his models to be there, to share that moment with him. That was a real bond, and now Donatella and Allegra are like family to me. I trust them, they trust me, we spend vacations together." (Campbell has the hybrid accent and vocabulary specific to those who have spent their adult lives flying back and forth across the Atlantic: she will say "vacation", but in the next sentence pronounce "little" the south London way, with the Ts almost silent, reminding me of the girl whose mum taught her to catwalk in the corridor to a Lionel Richie soundtrack.)

The most extraordinary of all Campbell "greats" has been Nelson Mandela. He is critically ill in hospital on the day of our shoot. "I am so blessed to know him, and I always ask why it was that I was able to meet such a great man. I am in touch on a daily basis. He's a strong man. The whole world is praying."

Campbell believes that the late 80s to mid-90s were not just her own glory days, but the golden age in which to be a model. "In my era, we'd get a phone call from John [Galliano] before the show: this is what the show's about, what do you think? And we'd talk about it; we knew what the inspiration was, we really understood the collection and where the designer was coming from and so knew what kind of vibe to have." As the fashion industry has expanded, the models have been sidelined, she believes. "If we [Christy, Campbell Linda etc] were on a different level to the models now, that's because we had a relationship with the designers, so it was a real collaboration. And the photographers, too – we were so close to Steven Meisel, to Mario [Testino]. When I started, the designers saw you in the castings and chose you. We went for dinner and hung out. Now you've got casting directors, and production. There's more of a gap between the model and the designer, because there are all these other people in the middle."

She is particularly concerned about the marginalisation of black models in the fashion industry. If she and her contemporaries spearheaded an era of progress in which different ethnicities were celebrated on magazine covers and catwalks, the past decade has seen the proportion of non-white faces on a downward trajectory. "I feel very responsible for young models of colour. They come to me and tell me they're not getting jobs, and I do what I can to speak up for them. This year has not been great. It's so disappointing. I feel it very personally. I've given 27 years to this business and things haven't got any better. It is shocking." Along with Iman and Bethann Hardison, an iconic black model of the 1970s who went on to found a model agency, Campbell is working on an initiative that is as yet under wraps. "We have to speak up, because we can."

These days, Campbell models on her own terms. When she takes to the catwalk, she does so as a special guest of the designer: most recently, she took the prestigious opening and closing spots at the Versace haute couture show, in Paris in July. (Backstage, Donatella remarked to me that Campbell was "still perfect. Look at those legs! They are amazing." She spends much of our shoot in hotpants and they are, indeed, amazing.)

For the seven hours she is on the shoot, Campbell never raises her voice or stamps her foot. When she is on set, in front of an audience, she exaggerates her ice queen persona, whether consciously or not: the eyebrows are raised higher, the acid asides delivered in an even more staccato tone. At these moments, she reminds me a little of Cate Blanchett or Tilda Swinton, in their snow queen/white witch roles. This makes me wonder whether her skin colour subconsciously affects the way we perceive Campbell. In the runup to the US presidential election of 2008, I read that Barack Obama worked on exaggerating the calm, unruffled delivery of his public speaking because the merest hint of heated emotion from a black man would be read by the public as a sign of temper, a hint of violence.

Does the colour of Campbell skin make us more likely to interpret her behaviour as intimidating, as difficult, rather than simply as aloof, or withdrawn? I ask her whether she believes the public notion of her character is an accurate one. "Well, everyone has a temper. A temper is an emotion. But do I care what they say? Is that what you're asking? Everyone is entitled to their opinion."

And what about your opinion, I ask? Are you happy with the way you are? "I'm a work in progress. But yes, I'm happy with the way I am now. I'm very observant and very instinctive. In life, you have to have the vulnerability to accept when you are to blame. And I do have that and I am open enough to say it. I've made mistakes. You know all that stuff, I'm not going over it again. And I admit to them, but I don't regret anything. I don't live in regret."

She goes silent for a moment. I am formulating my next question, when she declares: "Am I bossy? Absolutely. I don't like to lose, and if I'm told no then I find another way to get my yes. But I'm a loyal person. And I'm generous and I don't bullshit."

Being a model requires more mental strength than most people realise, she says; that is what she hopes The Face will show people. "You have to be able to take direction, you have to be always watching your composure, your attitude. But you have to be able to hold on to your own personality, too. That's the part you can't teach. On the show I tell my girls: this is a competition. You know what? You don't want to get so comfortable that you forget that, because you need to always be competing. You're not here to make friends."

• The Face is on Sky Living from 30 September.

Has Harper Beckham started a trend? Who is the new DVF? And what's the key piece for spring/summer 2014? Here's all you need to know so far from the New York catwalks

1. Alexander Wang is the new Marc Jacobs

The Wang runway has taken over from Marc Jacobs's as the show whose crowded bleachers provide an of-the-moment snapshot of who's who in Manhattan life. Kanye West, Courtney Love, Kerry Washington and Solange Knowles all cosied up for Wang at the weekend. Wang's stock is sky-high, now that he has the blue-chip Balenciaga job alongside his own label; meanwhile, Jacobs's show has moved to the back-end of the week, and has punctured its sceney-ness with punctuality.

2. Victoria Beckham is the new Diane Von Furstenberg

For decades, DVF has had the fashion industry eating out of her hand thanks to her peerless way with a quote about Being A Modern Woman, and her ability to back up aforementioned quotes with day-to-evening dresses that make you look hot and smart. This week, Victoria was chatting backstage about the "huge juggling act" of working motherhood, and singing the praises of her trompe l'oeil skirt-and-shirt dresses: "It's great to have something that you can just stand in, zip up and go."

3. No one eats anything remotely normal

Acceptable NYFW snacks: miniature lobster rolls at the Standard hotel or tempura green bean canapes at parties. (FYI: Alexa had deep-fried okra at her London book launch. Deep-fried vegetables are officially a thing.) On the whole, showgoers subsist on green juice, especially the kale kolada. Also, everyone Instagrams photos of cronuts. Do not be fooled by this: no one is eating them.

4. Rita Ora is now a fully fledged fashion player

As evidence: first, her assured catwalk finale at the DKNY show. It takes serious guts to follow Karlie Kloss on to the runway. Second, the prevalence on the catwalk and among the streetstylers of the Rita Crop, AKA the waist-length, loose top that shows just a couple of inches of flesh when paired with a skirt or a cute pair of skirts. The girl has influence.

5. Pastels are shaping up to be a 2014 trend

Sugary pale shades have broken out of the Ladies Who Lunch enclosure this NYFW. Pale pinks and blues opened Alexander Wang, and dominated the hip Creatures of the Wind show, while Ralph Rucci favoured peach, and got rave reviews in return. Prabal Gurung went so far as to make the case for favourite Nana-soap-shade, lavender.

6. The long loose dress is going to be a thing

When Victoria Beckham stepped out in front of editors, buyers and paparazzi on Monday she did so in a midi-length, cocoon-shaped, drop-waisted blue dress from her Victoria by Victoria Beckham collection. Not just that, she made a point of telling editors that she still felt sexy in it. At the Olsen twins' label, The Row, frocks were bigger (and better) than ever. Cheering news for those who prefer room to breathe (and eat) in their summer wardrobe.

7. Tennis is now the last word in chic

It had to happen. The influence of Anna Wintour knows no bounds, and everyone knows that Anna loves tennis as much as she loves Prada. This New York fashion week, the US Open front row was almost as glam as the shows: Justin Timberlake joined supermodel Miranda Kerr and actors Leonardo DiCaprio and Jessica Alba in the VIP seats for the final. Meanwhile, on the catwalk, a trend for pleated white skirts and front-row lust for the deep V-neck cotton sweaters at Rag & Bone nodded to retro on-court chic.

8. Tiffany could be poised for a comeback

If you haven't opened a little duck-egg blue box since your 21st, listen up: the brand is poised for a comeback. As if it wasn't enough that Harper Beckham sported a Tiffany diamond necklace this week, the brand announced the appointment of British jewellery designer Francesca Amfitheatrof as creative director. Amfitheatrof, who has created jewellery collections for Chanel and Marni, told WWD that she planned to "challenge the Tiffany customer" with her designs.

9. The skirt is your wardrobe's key piece

Still asserting your authority with a power jacket? Do try to keep up. The statement skirt, worn with a plain button-down shirt, is the modern way to do bold, dressed-up separates. Altuzarra, the latest label to have attracted investment from Kering – industry mothership behind Alexander McQueen and Balenciaga – made skirts split to the thigh the centrepiece of daywear for next spring. If your eye is drawn to the skirt first, that's a truly modern outfit.

10. Justin Bieber is reclaiming the Bieber fringe

Justin Bieber turned up at the Y3 show sporting a return to the signature swooshy side-flicked fringe with which he melted a million teenage hearts. Presumably, media rights surrounding a Nickelodeon-sponsored fringe-off between Bieber and Harry Styles at the next Teen Choice awards or similar are being thrashed out as we speak. Bieber is also sporting a nascent moustache, but rumours that he is getting a headstart on Movember are as yet unconfirmed.

Jess Cartner-Morley picks out some of the most interesting items for your wardrobe

What to look out for, from newcomers Barbara Casasola and Claire Barrow to Manolo Blahnik's LFW debut

JW Anderson

The buzziest young designer on the schedule, thanks to a fortuitously timed rumour, which emerged this week, that the powerhouse luxury stable LVMH is considering making the Dalston-based designer an investment offer he can't refuse. Whether or not Anderson follows in the footsteps of Christopher Kane – whose label recently joined the Kering stable – his show on Saturday afternoon is sure to be packed to the rafters.

Barbara Casasola

Brazilian-born and Central Saint Martins trained, Casasola is a hotly tipped newcomer to the London fashion week schedule. She learned her way around a seriously sexy frock with two years as Roberto Cavalli's right-hand woman, and has since been working in Paris for Lanvin and See by Chloé. She is shortlisted for the prestigious Dorchester Collection fashion prize, which will be announced in October.

Manolo Blahnik

Bath's best-shod resident, Manolo Blahnik, has designed shoes in the UK for over four decades – but this week marks his debut on the London fashion week schedule. On Sunday, he will host a screening of a short film starring his latest collection of sublimely elegant shoes.

Claire Barrow, Ashley Williams and Ryan Lo

Lulu Kennedy's Fashion East stable has a blue chip pedigree as the nursery slopes on which British fashion's most talented, most fun and most original names pick up speed before hitting the big time. Claire Barrow's hand-painted leather jackets are currently an in-crowd favourite among the fashion industry.

Burberry

The Burberry catwalk formula is simple. Pack the catwalk with supermodels, cram the front row with stellar celebrities, style the collection into slick, trend-focused looks which gain traction at fashion's street level, add a heartstring-tugging soundtrack of Christopher Bailey's latest singer-songwriter favourites – and finish with a flourish of technical wizardry. Burberry are collaborating with Apple this season, with photos and video from the catwalk and backstage being shot on the new iPhone 5S, four days before it goes on sale.

British Fashion Council concerned that high tuition fees and living costs will block emergence of next generation of fashion greats

British fashion is a success story of the moment. An estimated £100m worth of orders will be placed by those attending the 58 shows at London fashion week, with £74m of those funds coming from abroad. But the pipeline of creative talent which feeds the industry is in serious danger of drying up as tuition fees prevent talented young British students taking up places at world famous colleges such as Central St Martins.

This was the stark warning given by the British Fashion Council even as the champagne flowed to mark the first of the week's shows, at Somerset House on Friday morning.

"All the greats of modern British fashion – McQueen, Galliano, Kane – have come from working-class families," said Sarah Mower, the BFC's education tsar and a visiting professor at Central St Martins. "That is the story of British fashion." The current crop of successful home-grown names "came through at a time when fees didn't exist, or were affordable," she added.

Such is the level of concern that the BFC has made education the primary message of this LFW. "Our world-famous fashion colleges play a key role in what makes British fashion fantastic," says chief executive Caroline Rush. "When you talk to [star designer] Jonathan Saunders, he is very frank and straightforward that he wouldn't have been able to become a designer if he had been faced with the fees now being charged. We are really concerned that fees, and the cost of living in London where many colleges are based, will prevent the next generation of talented British students from non-privileged backgrounds from coming through."

The British fashion industry is being urged to follow the American model where industry, alumni and philanthropists "give back" by bankrolling bursaries and scholarships to boost the next generation of talent. Marks & Spencer, the first British business to sign up, announced on Friday that it would underwrite an annual BA degree, beginning next year. "Marks & Spencer are the first on board, and we are aiming to get from one to 10 pretty quickly," said BFC chairman Natalie Massenet. "It is paramount that we secure London's reputation for producing the best fashion talent."

New York-based label J Crew is marking the opening of its first London store this autumn by paying for three year-long bursaries to CSM students, covering tuition fees and accommodation. Meanwhile, London mayor Boris Johnson wants to focus on encouraging British-educated fashion students from abroad to start their businesses here, by extending the "fast-track"visa system for candidates of exceptional ability to apply to fashion design. Johnson this week described the plan as "a clear message to … the fashionistas of Beijing that London is the place they should come to develop ideas [and] build new businesses".

But while the loudest rallying cry is to titans of industry, Massenet is also reaching out to London's army of street fashionistas, urging the city to "dress up" for fashion week. "In New York everyone knows when fashion week is on – it feels like fashion week. I want it to be the same here," she told Vogue recently. She has written to all the week's participating designers, encouraging them to use social media to make as much noise as possible about LFW and create an appetite for fashion that extends beyond the show venues. "This is a moment not just to engage the people sitting in your front row, but to engage the people at home who would love to be there," says Rush.

The BFC has scored a coup in signing up Google's Peter Fitzgerald as head of innovation. Fitzgerald has described the role as "a fantastic opportunity. There is so much growth opportunity for fashion brands to harness the power of technology, both for showcasing and e-commerce. Through demystifying the digital landscape, we aim to empower British designers to build their brands on a global stage."

Despite the stark warnings about an industry in imminent danger of being starved of the oxygen of talent, the formidable Massenet also turned the London rain into a positive. "It was such beautiful weather at New York fashion week," she said, "so I'm happy we've one-upped them by giving fashionistas the chance to wear their new autumn fashions."

'September fashion is about tailoring, or new hemlines, or zingy colours. The sleeveless coat is the perfect first autumn buy'

You know that feeling, when you get back from holiday? When you unlock the front door and the telly's still there (haven't been burgled, phew), your keys make that same clatter when you drop them on the hall shelf and you put the kettle on? While you're waiting for that first proper cup of tea in a fortnight, you start watering the plants, some of which seem to be as close to thriving as they were before you left, and in a calm, quiet kind of a way you feel quite at peace with the holiday being over?

By the end of summer we have gorged on ice-cream pastels, worn our denim threadbare; we have bottomed out our obsession with flat sandals that are rope-soled, ethnic-beaded and/or gladiator-strapped. In short, we are ready to start dressing like grown-ups again. September, when the magazines are fat and tempting, and the air crackles with post-holiday good intentions, is the season of renewal. A bit like Easter, but with less chocolate, what with some of us having gorged on actual ice-cream as well as the pastels.

September fashion is about tailoring, or new hemlines, or zingy new colours. This year, the sleeveless coat is the perfect first autumn buy. (Eagle-eyed catwalk spotters will have noted the look on the Prada catwalk a full year earlier, but it was at the catwalk shows for the current season that the look took off, notably at Victoria Beckham's show.) But crucially, what with us being barely unpacked from hols, it doesn't entirely cover you up. On the catwalk, Beckham's sleeveless coats were worn over trousers and smooth, second-skin polo-neck sweaters, but when Beckham herself was first photographed in the look, stepping off a plane in Beijing, she wore it with trousers and a shell top, with toned, tanned arms.

The sleeveless coat is a new-season top layer you can wear now, with layers for warmth to be added later. What's more, as an I'm-not-on-the-beach-no-more memorandum to self, it will kick your look into gear. In the chess game of fashion, it is a classic opener: bold and eye-catching, but tactically sensible. Because silly season is over.

• Jess wears coat, £625, by Alexander McQueen, and trousers, £355, by 3.1 Phillip Lim, both harrods.com. Courts, £55, office.co.uk.

Styling: Melanie Wilkinson. Hair and makeup: Sharon Ive at Carol Hayes Management.

Tom Ford, Alexander McQueen, Longchamp and Paul Smith unveil new or refurbished stores to mark sartorial celebration

"British customers are among the most discerning and stylish in the world," says Tom Ford of his investment in a London store which opens this weekend.

Ford is not alone in this view. London fashion week will also see the opening, or upgraded reopening, of new landmark boutiques for Belstaff, Alexander McQueen, Longchamp and Paul Smith.

The trend for retail muscle-flexing on Bond Street, Sloane Street and Regent Street reflects a resurgence of self-confidence in the British fashion industry, as well as the nascent economic upturn. British Fashion Council chief executive Caroline Rush believes that they are "a great signifier for London. British and international brands now consider London the go-to destination for fashion."

Bond Street will be closed to traffic on Saturday evening for a motorbike parade celebrating the opening of the Belstaff store. Harry Slatkin, vice-chairman and chief executive of Belstaff – the recently revived British luxury label whose motorcycle jackets have been worn by Hollywood stars from Steve McQueen to Johnny Depp – said this week that he "wants the British Fashion Council to know that we are committed to helping establish London as a major fashion capital".

In fact, the style and ambition of the new retail palaces suggest London is already secure in its status in the fashion world.

Sarah Burton will unveil the first new look for an Alexander McQueen store since she took over on the death of the designer. In the store, moulded plaster panels feature wings, shells, cactus flowers, mushroom gills, seahorse tails and the skulls that are a house motif. The velvet sofas feature solid bronze animal feet: gazelle hooves and monster claws.

"It's very McQueen to see something from a distance and think it's one thing and then to look up close and discover something else," said Burton of the design. At Paul Smith's new Mayfair store, a trio of small drawings by Smith are cast into the facade's iron panels. "We talked about the element of surprise always found in Paul's clothes," said architects 6A of the project.

Tom Ford, legendary for his insistence on 360-degree control over every element of his company and brand, has devised the ultimate finishing touch: a perfume specifically created for the store. Private Blend London is described as a "rich and spiced, woody animalic fragrances [which] captures London's cultural vibrancy and unique dynamic between elegant, urbane composure and sometimes scandalous carnal amusements."

Scott's London collection steals the spotlight from rock star boyfriend, while Emma Hill presents her final Mulberry collection

• Live coverage of all the action at London fashion week on the Guardian live blog

When fashion designer L'Wren Scott moved her catwalk show from New York to London earlier this year, she had one significant concern: "I was worried that in London I would be judged for who I know, rather than what I do. In New York, I am known for fashion." Scott, a designer with a two-decade backstory as one of the most powerful red-carpet stylists in Hollywood, is still better known in the UK as Mick Jagger's girlfriend.

But London's high stock of cultural capital persuaded her the time was right for a show here. "People all over the world pay a lot of attention to what happens in London," she said.

"Last year with the Olympics, the Jubilee, every great art show being here, it just felt more than ever like the epicentre – and as a creative person, that's where you want to be."

On Sunday at London fashion week the formidable Scott, who stands 6'3" in her handmade brogues, showed for the second season that her clothes are quite capable of stealing the limelight from the diminutive rock star seated next to Anna Wintour.

Scott delivers the Oscar-level glamour achievable by dresses which are not only painstakingly tailored to create a knockout silhouette, but embellished and crafted into works of art. A 16th century Japanese screen decorated with drawings of kimonos, seen in a museum, gave Scott the starting point for bandage-tight dresses delicately embroidered with cherry blossom, a Tokyo-inspired take on Le Smoking, with a kimono-wrapped jacket fastened with an obi-style belt, and bento box red tailoring with the origami folds at the collarbone which Roland Mouret has long since used to flattering effect.

"What resonates culturally with me about Japanese style is that it is very covered up, but very sensual," said Scott, interviewed before the show while casting models in her Chelsea studio.

Staging a show at London fashion week, traditionally squeezed between New York and Milan, still has "practical challenges", said Scott. "You don't know which models will be in town until they walk through the door for casting, and I find that hard because I'm not naturally a last minute person. I like to be organised."

Scott has an alpha female aura which succeeds in infusing the clothes, drawing like-minded women to them: in the US, Michelle Obama and Oprah Winfrey are regular L'Wren Scott wearers. Scott will not, however, be drawn on names of potential high-profile British ambassadors. "I love seeing women looking great in my clothes. I don't care who they are. I don't quantify people by celebrity," she said.

While Scott was amplifying her voice in the British fashion chorus, another female designer was saying her farewells as Emma Hill, the designer at the helm of Mulberry for the past six years, presented her final collection.

It was Hill who brought Mulberry, previously an accessories brand, onto the catwalk schedule, a move which transformed the brand's image and profile. However, after the appointment last year of Hermès's Bruno Guillon as Mulberry's CEO, there were rumours that Guillon's ambition to create a fully-fledged luxury brand clashed with the image of down-to-earth, approachable glamour which Hill created.

In June, it was announced that Hill would be stepping down by mutual consent. "Mulberry's essence is its inherent Britishness," said Hill yesterday, summing up her tenure. "Not as a pastiche but as a real and fundamental part of the brand. Mulberry pioneered the desire for "Le Style Anglais" in the 1970s and that celebration of beautiful, practical things is still a big part of the collection."

The quintessentially British tradition of afternoon tea – a ritual which, with its crustless sandwiches and miniature cakes, is decorative as well as practical – set the scene for Hill's final show, with miniature Wedgwood tea cups sent as invitations and tiers of scones and crumpets flanking the entrance.

The children's song If you're happy and you know it blared as Cara Delevingne and Turbo the bulldog vied for supermodel status on the catwalk in Claridges ballroom, and a rousing blast of Land Of Hope And Glory closed the show. Before the show, asked about her feelings about the swansong, Hill insisted that it was simply business as usual.

"Each time my team and I spend a week in each other's pockets, like a big fashion week boarding school, it's very emotional." Nonetheless Hill, whose next move is yet to be revealed, was overcome backstage as she thanked her team, many of whom were in tears. "You lot, you'll always be my Mulbs, and I love you all," she told them.

Collection showcases first ethically produced outfits by five of the UK's most prestigious fashion houses including Burberry

The raison d'etre of fashion week is to challenge the status quo. A catwalk show exists to put a desirable spin on a newer, more modern way of doing things – and therefore nudge the world forward, a half-inch hemline-shift at a time.

The most glamorous new collection showcased at this London fashion week was aimed at bringing about a more significant change in the way we dress, shop and think than a new dress length. American Vogue editor Anna Wintour, actress and ethical fashion campaigner Livia Firth and Natalie Massenet, chairman of the British Fashion Council, hosted the unveiling of the first ethically produced outfits by five of the UK's most prestigious fashion houses.

Burberry, Victoria Beckham, Christopher Kane, Erdem and Roland Mouret have all designed "green" dresses, the production of which meets the social and environmental benchmarks devised by the Green Carpet Challenge as a kitemark of ethical fashion. The clothes will go on sale on Net-a-Porter, the online retailer founded by Massenet, with 20% of each sale being donated to the Global Fund's campaign against Aids, tuberculosis and malaria.

This first Green Carpet Challenge collection aims to break down barriers, both real and imagined, between mainstream and ethical fashion. Christopher Kane, who attended the launch after staging his own successful catwalk collection the same day, said he hoped the collection would show ethical fashion could be "glamorous and achievable". The collection takes the principles of Livia Firth's Green Carpet Challenge – a campaign to change perceptions of "green" fashion by showing that ethical frocks can hold their own in the glamour stakes – and extends it to ready-to-wear, so that ordinary shoppers can apply the Green Carpet principles to everyday life. By embedding ethical clothes in the supply stream of mainstream fashion, Firth hopes the collection can bring about "systemic change". And by enlisting A-list designers to the cause, the Green Carpet Collection is also designed to banish the hair-shirt connotations that continue to linger around ethical fashion.

Designer's London Fashion Week show held just as Christopher Kane's flagship store in Mayfair is announced

The spotlight suits Christopher Kane. Eight months after signing a major deal with luxury mothership Kering, which fast-tracked his tiny company onto the path to major label status, on Monday he staged one of his best London fashion week shows to date.

Kane is flourishing by embracing the advantages of life in the fast lane while keeping a foothold in reality. Just three hours before the show, Alexander de Brettes, the label's recently appointed CEO, announced that Kering will bankroll a major Christopher Kane boutique, to open in Mayfair next year. The flagship, on Mount Street, will put the Kane label alongside Balenciaga, Christian Louboutin, and Lanvin. By contrast, the catwalk show was staged in the Farmiloe building, a near-derelict warehouse near Smithfield meat market that has been unoccupied since 1999.

The funds now at Kane's disposal were evident in some aspects – a no-expense-spared cast of 54 models walked in the show – but backstage the designer still had pins tacked to his T-shirt, the better to effect last-minute adjustments before the runway. And when asked whether the high-tech fabrics on the catwalk were evidence of more money to spend on fabric production, he looked aghast. "I ironed and bonded those garments myself," he said. "I mean, maybe we could afford to get someone else to do it – but if I don't do it myself, it won't be right."

This collection was about flowers. "But when I say flowers – I'm not going to do, you know, roses, done to death, blah blah blah." Instead, it was "the sexual undertones of flowers", of anatomy and deflowering, which formed the starting point for the clothes. A visit to his Scottish high school brought back memories of art classes spent dissecting, examining and drawing buttercups and carnations. "I started thinking about how much we take flowers for granted, and how incredible they are, and how the female sexual organs have so much in common with the internal structure of a flower. When I was growing up, my mum always used 'flower' as her word for vagina – it's a Scottish thing. I prefer sex to be an undertone in my clothes, rather than too obvious, so I was interested in how flowers are graphic but concealed and suggestive at the same time."

Jean Cocteau said that style "is a simple way of saying complicated things." Viewed as sartorial self-expression of the point at which Kane now finds himself, the flower symbolism seemed double-edged. Sweatshirts emblazoned with the words 'FLOWER' and 'PETAL', and dresses embroidered with snippets of botanical diagrams of life cycles, seemed to celebrate the notion of a humble seed growing into something glorious. On the other hand, the theme of deflowering is hard to divide from loss of innocence. And the evening dresses in slippery satin, ruched and clasped with crystal reimaginings of the metal clips used in school dissection seemed vaguely sinister in origin – although, in true contradictory Kane signature style, these dresses were among the most elegant and desirable on the catwalk.

The shift in identity toward becoming a grown-up luxury brand was most evident in the catwalk in a very simple way, in the longer hemlines, which fell to the most part on or just below the knee. The Kane label is no longer aimed just at twentysomething "It" girls, but at a more womanly international clientele, who is less inclined to wear a micro-mini.