The extra layers you need to take you into autumn.

Dressing in September can be a tricky art to master, even without the whole climate change thing that’s going on right now. Wearing a camp-collar shirt sans jacket is a little too risky when the temperature’s veering from summery to autumnal, yet wearing your heavy winter coat is far too premature. So, when it comes to dressing during these capricious in-between months, we highly advise that you focus on lightweight, durable or – if needs be – waterproof jackets (yes, waterproof; we are writing this from MR PORTER’s London office, after all) that can handle any meteorological scenario.

With that in mind, we’ve picked out some of our favourite bits – from zip-up track tops to bright red Harringtons – that will see you through the rest of summer, autumn and beyond. You can thank us later.

It doesn’t seem so long ago that the cardigan was seen as the reserve of librarians and ageing poets; something to be filed alongside shearling-lined slippers and smoking a pipe. How times have changed. Today’s cardigan is smart, stylish and super versatile, and it’s as much a wardrobe staple as the classic crew-neck sweater. Particularly useful are the zip-up varieties, such as this merino wool example from Belgian designer Dries Van Noten. Wear it with a black T-shirt and tapered trousers to nail mid-century cool. Or, smarten it up and layer under a blazer for when the temperature dips.

An overshirt – or shirt jacket, if you like – is one of the best buys for seasonal ambiguity. It’s rugged and it’s utilitarian. It’s a little more polished than a hoodie, and it looks great underneath serious outerwear come winter, too. This season’s offering feels especially rich with options. Take Mr Virgil Abloh’s version for Off-White in a vivid blue check – a contemporary take on the classic lumberjack style and cut in a boxy silhouette that’s easy to throw on (unbuttoned) over a white tee or sweater.

The denim jacket is an item of clothing with near-universal appeal. And no wonder, given that it suits every body shape, is practical, affordable and only gets better with a bit of wear and tear. Plus, you can dress it up or dress it down depending on your needs. If you’re the sort of guy who likes everything in your wardrobe to have both a whiff of authenticity and a pre-loved, heritage feel, then this piece by A.P.C. is the one for you. It looks charmingly retro thanks to the washed-out Japanese denim used in its construction. A word of caution though: if worn with jeans, the denim of the jacket should be a lighter shade.

The sportswear revival that has swept through menswear over the past few years has seen a reversal of fortune for the zip-up track jacket. Once the reserve of 1980s athletes and football terraces, it is now a versatile and stylish throw-on. You can slot a track top under an overcoat. You can wear it over a T-shirt. You can stow it away in a bag if you need to. And there’s no need to raid the attic to find one either, thanks to this season’s clean, minimal takes on the classic retro style. Valentino’s version offers a perfect way to try out a vintage sportswear look without being too flashy. If you’re brave enough, then go for the full warm-up look with the matching sweatpants. If not, then tailored black trousers and a pair of Common Projects will do.

An iconic piece of menswear that has been favoured by the likes of Messrs Elvis Presley, Steve McQueen and, perhaps most famously, James Dean, the Harrington jacket is still as smart now as it was when it first left the factories of Baracuta (the originator of the style) back in the 1930s. Defined by its bomber-like fit, but with a standing two-button collar, the Harrington caters to the most necessary of needs: it’s thin enough to wear in summer, it blocks out the wind and rain come autumn, and it’s lightweight enough to be worn under a jacket or over a T-shirt. It’s almost impossible to look at this one by British brand Burberry and not think of Mr Dean in Rebel Without A Cause. Take his style cue and keep everything else simple with black jeans and a crew-neck tee.

The hoodie (or hooded sweatshirt) has done a long stretch in fashion rehab over the past few seasons, thanks to the increasing influence of street style on young designers (namely Messrs Demna Gvasalia and Virgil Abloh). Our favourite of the current crop? This one in green by Aimé Leon Dore, an American brand that take its cues from old-school street culture in Queens, New York (everything from hip-hop to pickup basketball games serve as inspiration). Made from soft cotton jersey and cut to fit comfortably, it will look as good worn with jeans and sneakers as it will with a pair of shorts and some slip-ons. Plus, come winter (sorry to beckon the cold), layer it under your overcoat for a clever yet stylish mix of high and low.

In this, the golden age of the designer hoodie, it’s tough for other forms of sweater to get much airtime. That’s especially true of the cable-knit sweater, which is diametrically opposed to the hooded sweatshirt in its sophistication and seriousness. Ah, but designers are clever: they’ve found a nifty workaround to ensure that the style remains disarmingly fresh. Instead of sticking with the usual muted colors (very heritage, but very samey) that typically accompany the style, many have opted them in eye-catching hues. Take AMI’s sweater in vivid yellow merino wool – it’s the perfect throw-on for chilly evenings out or cosy weekends at home. Try it on with a pair of light-wash denim jeans a pair of chunky black Derby shoes to channel Parisian cool.

It’s too early in the year for heavy wool blazers, and those of the linen and seersucker variety are best saved for holidays abroad, or the hotter days of summer. But a lightweight blazer in cotton poplin can be exceptionally useful at this time of year, especially when you’ve got smarter dress codes to adhere to. If your office is anything like ours, where you spend most of the day at the mercy of an air-conditioning system, then a smarter jacket in a mid-weight fabric is a smart way to avoid the cold. They’re invaluable for the alfresco dinners in the evenings, too, when the temperature has a habit of plummeting as soon as the sun dips below the horizon. Aspesi’s unstructured navy blazer – exclusive to MR PORTER– offers a stylish solution to your woes. Throw it on over a classic white shirt and chinos combo for a look that’ll satisfy all but the most formal occasions.

Is there anything better after a long, hard day in the office than kicking off your Cheaney shoes, hanging up your Kingsman blazer and throwing on a crisply ironed pair of pyjamas? Sweatpants and treasured tees from your university days have their place, but save them for hangovers. Pyjamas are perfect for an evening in watching Scandinavian boxsets. This pair by English heritage brand Derek Rose in navy herringbone check by is made from a lightweight cotton which feels great on the skin and is ideal when you’ve got to crank the heating up come September. Now all you need is a pair of comfy slippers and a cuppa.