I don’t want to look retro. I think victory rolls are twee and I would not be seen dead in a nylon petticoat. I will go for a bare leg over a seamed stocking every time. Right now I want a cardigan that I can tuck into a midi skirt, but I want it sleek and neutral like the ones on the Chanel autumn/winter catwalk, not in a fuzzy pastel with embroidered flowers. So today, Mel Wilkinson, the Guardian’s stylist – a vision of contemporary chic in understated neutrals – and I have set ourselves a challenge. We are going secondhand shopping, but for this season’s looks. Can we find now clothes, without buying new clothes?

Buying clothes secondhand is, after all, very fashionable. This is sustainable retail therapy, a feelgood fashion fix that doesn’t add to the environmental problem of clothing overproduction. In the US, the resale market has grown 21 times faster than the retail market in the past three years, with a ThredUp report this year predicting that the secondhand market could overtake fast fashion within a decade. In the UK, the younger generation of shoppers are returning to a taste for secondhand that their parents’ generation, raised on a ready-made diet of fast fashion, never cultivated. Eighty per cent of 16-21 year olds are happy to buy secondhand clothes – second only in their enthusiasm to the over-60s, of whom 90% are comfortable buying used garments – while less than a third of shoppers in their 30s and 40s are on board, according to a survey by Business Waste, a waste management agency.

If you want to find clothes that look current, don’t look at the labels – zoom in on colours

The new higher profile of secondhand shopping is beginning to be felt on the high street. In Covent Garden in London, a new branch of Picknweight, a vintage kilo store that is already a cult destination in Berlin, had customers queueing down the street when it opened. Mel and I start our hunt for now-clothes-not-new-clothes next door, in the Shelton Street branch of Rokit, a vintage institution which has resold more than a million tonnes of preworn clothing since the first branch opened in Camden market in 1986. The shopfloor is vast, but Mel is dauntless. “Most vintage shops curate their pieces in a way that reflects current trends,” she says.

In minutes she has unearthed a tan leather shirt – very Loewe, but a fraction of the price at £25.

Secondhand hunting requires you to up your game as a shopper. Walk into a high street store and you will see ready-made looks, glossily presented on mannequins and helpfully merchandised with stock in different sizes and coordinating items. In a secondhand store, you have to move slower and look harder. You have to rewire your brain a little bit. It helps to remind yourself that while new clothes look the best they will ever look fluffed and spotlit on the shopfloor, secondhand is the opposite – these pieces undersell themselves on the shopfloor and come into their own once you get them home.

Perfect for this season … from left: 80s-style dress, £34, and sequinned top, £28, both at Beyond Retro. Tiger print blouse, £30, and argyle sweater, £28, both Rokit. Dress, £29, Beyond Retro. Composite: Guardian Design; 100% Digital/The Guardian

Clare Lewis, founder of an online vintage boutique Retold, has a robustly non-retro aesthetic, having spent a decade designing for Topshop. “I started Retold to encourage people to see how vintage could be incorporated into a modern wardrobe and look contemporary, in the hope they would be inspired to shop vintage as an alternative to buying new,” she says. This is a great season to source vintage because “so many trends lean towards the 70s, 80s and 90s”.

She tips hunting for trenchcoats, blazers, midi skirts and blouses to channel the bourgeois-lady look, as seen at Chloé and Burberry. Leather, as seen at Bottega Veneta and Isabel Marant this season, should be on your contemporary-vintage hit list, too. Leather is abundant in secondhand stores, but Lewis suggests narrowing down your shortlist by concentrating on tailored pieces in neutral, tonal shades of brown or grey.

If you want to find clothes that look current, rather than designer bargains, don’t look at labels. Instead, zoom in on colours – anything beige, tan or gold is great for now. Or look for the skirt length of the moment – somewhere between midi and maxi. Rokit has lots of great silk blouses. We find a particularly good leopard print – very next-season Celine, down to the gold lurex thread running through it. Argyle-knit sweaters, as seen on the Gucci catwalk, are here too – there is a nice, snug burgundy one, in perfect condition, for £12. A tweed blazer with an embellished jewel collar is really quite Prada, and only £45. If 90s sportswear is your thing, you are spoilt for choice – lots of Reebok and Adidas hoodies, for about a tenner each.

Jess and Melanie with their secondhand finds. Photograph: Jill Mead/The Guardian

Holly Watkins is another fashion industry veteran and the founder of the online vintage boutique One Scoop Store. “The preconception with vintage is that it’s all brown 1970s polyester dresses, massive leather jackets or badly fitting tweed skirt suits, but that’s just not the case these days.”

Her online edit features Molly Goddard-esque ruffles, brightly coloured tailoring and 70s-style chiffon and lace. “I recently had in an incredible geometric print kaftan dress cut in a circle, which was very similar in shape to a Margiela one I own. Another of my favourites lately was an emerald green metallic 1970s maxi which the customer styled with white leather ankle boots – the result was so modern,” she says.

From Rokit, Mel and I move on to Beyond Retro, a warehouse-sized Aladdin’s cave of a shop near Brick Lane in east London. A flick through the rails soon turns up treasures: a tailored long-sleeved brown dress with a white, pearl-studded wing collar – very this-season Victoria Beckham for £29 – and a 1980s party dress with draped neckline and shoulder pads in glittery black velvet, which is pure Anthony Vaccarello-era Saint Laurent, for £25. To go with it, a beaded evening bag is just £9.

There are racks of trenchcoats, piles of corduroys and acres of high-waisted denim, as well as a treasure trove of non-trend pieces, from ski wear to weekend bags. The circular economy is perfectly suited to fashion’s self-referential trend system. “Fashion is cyclical, after all,” says Lewis. “You can pretty much guarantee that the original of what you are looking for will be out there.”