When people find out I work in fashion, they usually do one of two things: ask me to evaluate their look – awkward – or ask me, “What’s trending this season?” The second is actually the harder. That’s because, when it comes to menswear, being a la mode is less about some kind of seismic change and more about a twist. It’s a subtle wardrobe rejig: the length of your coat, or whether or not wearing a tie is in, rather than a sudden, dramatic silhouette shift.

A better question would be: how many clothes do I actually need? Thanks to the timeless nature of so much menswear, curating an evergreen capsule wardrobe doesn’t have to be complicated. Paring back your clothes to the very basics can prove divisive – some say there’s no fun in minimalism, while for others a sleek uniform edit is the peak of owning a style. Either way, we should all be aiming to buy fewer clothes, so the items that actually do make it into our wardrobes demand an extra level of consideration.

“Reducing your wardrobe to the fundamentals is a form of sustainability,” says Bill Prince, editor of Wallpaper*, whose wardrobe of grey and navy tailoring, mostly styled with a roll neck or shirt, is in many ways classically smart but crucially never stiff.

What is the magic number? Going by TikTok tutorials or books such as The Happy Closet by Annmarie O’Connor, 20-25 items seems about right. Mitch Hughes, menswear director at Marks & Spencer, agrees, though adds that this does not include socks or other accessories such as scarves and hats. “For most men a capsule wardrobe will be built around iconic pieces, which have been seen in different iterations for decades. It will range from casual items – a white sneaker or plain T-shirt – to smarter garments such as a wool overcoat, Chelsea boot or simple navy suit.” Creating a leaner, more functional wardrobe will, Hughes says, also make getting dressed a streamlined affair in the long run.

Miuccia Prada would know. While she might be credited in fashion circles with setting the trend agenda, she is a huge personal fan of uniforms – hers mostly revolves around an excellent skirt, a cashmere knit and mesmerising earrings – which she has suggested offer a certain comfort while mostly demanding zero thought.

As I have got older, my own wardrobe has narrowed and now offers more style security, less fashion controversy. It consists largely of striped shirts, from dependable Uniqlo to Comme des Garçons Shirt, alongside jeans, including vintage Levi’s and a newish pair from French experts APC. If my mood ever dips – I work in fashion, it happens – I jazz things up with arty knitwear I’ve collected over the years. Or I just Google Steve Jobs, whose preferred ensemble of black Issey Miyake turtleneck, Levi’s 501 jeans and New Balance 991 sneakers is a persuasive argument for uniform-dressing. I would count artists Gilbert & George’s neat, almost identical suits and Andy Warhol’s blazer and jeans in this category, too – their use of sartorial repetition is/was never boring. Owning an individual look – such as Jean-Michel Basquiat in clashing blazer and trousers, or his beloved Armani suits covered in paint splatters – is arguably just a more creative spin on a capsule.

However, nailing the classics – even as you edit and tweak them towards your own personal style – can be a good starting point for any wardrobe re-evaluation. Nick Wakeman, founder and creative director of the fashion label Studio Nicholson, whose design approach leans toward function over faff, doesn’t hesitate when asked how to start building a men’s capsule wardrobe. “Jeans. Black or blue,” she says. “There are so many ways you can skew jeans. You can wear them with a suit jacket or any tailored piece, and with sneakers or shoes.” They also transcend age brackets. As Hughes notes, “My dad is 84, I’m 50 next year and my son is 16, but all three of us would wear an indigo jean.” Sure, the shapes might vary, “and we might all wear them differently, but it underlines the importance of pieces that offer a certain timelessness and versatility”.

Almost everyone I speak to agrees that the suit is a crucial player. But not all agree as to what that suit should look like. Wakeman prefers more flexible tailored separates, such as a wearable blazer, as do I. But a suit can of course be broken up – far from this being sartorial sacrilege, Prince says he is increasingly seeing mismatched blazers and slacks being worn successfully, and given a more relaxed mood when styled with alternatives to starch-collared shirts.

It might sound obvious, but if you are investing in a capsule-friendly suit, choose something simple, neutral and devoid of trend affectations – I promise you, most men don’t need a purple suit or one with more than three buttons on the blazer. Spend as much as you can afford to and try it on with various options before you invest: smart shoes and trainers, for example, or different tops. Try knit layers – superfine cashmere round-neck tops from Johnstone of Elgin are a Wakeman tip – polo shirts and well-cut T-shirts.

Keeping a capsule wardrobe exciting is all in the styling. “Interesting layering can really energise individual pieces in your wardrobe and create new looks,” says the menswear designer Charlie Casely-Hayford. I ask what he would recommend for adding spice, something you might wear to a party. He suggests a camp collar (also known as a revere collar) shirt, possibly printed, maybe in silk. “I would wear it with a T-shirt underneath for winter with formal trousers and proper shoes, but remove the T-shirt in summer for a more relaxed look, possibly with sneakers,” he says. “You have to always think about how hard each piece is going to work for you.”

Coats can be a sticking point – two things to consider are obviously your local weather and your body’s own temperature. “I think a trench is more useful than an overcoat,” Wakeman says. “Or maybe an anorak? Or a cagoule?” All good for layering. Hughes, meanwhile, suggests the “commuter-friendly” gilet should be included in the final 28. This might be controversial for some because of its banker bro reputation, but it has certainly been elevated by the likes of Succession and “quiet luxury” brands such as Brunello Cucinelli and Loro Piana. Sidenote: even if you can’t afford those labels, study their in-store mannequins for styling and layering ideas. Prince advocates for a field jacket – a relaxed style rich with pockets.

While you don’t want to be blown in the winds of whatever is current in pop culture, creating a mood board is a really good idea. Wakeman makes them featuring the likes of Harrison Ford or Kim Basinger, when she is working on a new collection, and is a fan of looking at films or people on the street you think have nailed their style, then taking time to consider what it is about their look that works so well. How can you put some of their attitude into your own wardrobe? Having recently watched Leon, the 1994 film about a hitman starring Jean Reno, I would argue that a tailored wool overcoat worn with a white T-shirt is worth considering as part of a grownup capsule wardrobe.

Not sure where to start? Head to your wardrobe for a good old-fashioned clear-out – you will probably have half the things you need. “The hardest but simplest task is to go through each item in your wardrobe, and if you haven’t worn it for two years, get rid of it,” Prince says. It might sound like a harsh proposition, but as the late, great Vivienne Westwood once said, “If you love something, wear it all the time. Find things that suit you. This is how you look extraordinary.”