The Best Summer to Autumn Outfits for September

September’s arrival presents a wonderful medley of opposites, a magical moment of the dwindling summer season melting into the crisp colour palettes of autumn, a fusion of all the climates packed into one 30-day period before we banish our summer dresses to the loft and cloak ourselves in cashmere for the winter.

And though this month, an untidy interim between two clear seasons, feels like it gifts us both the nostalgia of sun-soaked evenings past and the fledgling fancies of hibernation, when it comes to what to wear, it is rather more a sartorial stupefaction than we might like. There are still whispers of a heatwave somewhere on the horizon, and so the question of how to keep summer pieces at the forefront of our wardrobes for a little longer without being caught short when the heavens open is one on the lips of every staunch vestiary up-and-down the country.

To support, Karen Millen has collated a checklist for the style-minded on exactly what, and how, to navigate the next month.

Leather Jackets

A leather jacket is perhaps the fashion world’s worst-kept secret when it comes to transitional dressing, but its widespread appeal doesn’t dampen the garments ability to toughen-up a summer look and give it impressive colder-clime credentials. Not only do they effortlessly take a more summery look to a trans-seasonal ensemble, they add timeless appeal to those pieces you like to pull out year-after-year. Plus, leather only gets better with age, breaking down and moulding to your form with time, meaning that it’s a piece you’ll be able to rely on every September from here on out.

Trench Coats

Having proved itself many a year-ago, a first-rate trench is a lifetime investment, suitable for every season. Originally designed as a military coat, the trench coat’s staying power has seen it take up a permanent spot in the fashion hall of fame and its transitional quality is second-to-none. The garment’s understated simplicity makes it the perfect way to temper a bright outfit, or to add a dash of professional polish to more casual attire.

Midi Dresses

The best midi dresses are hands-down one of the hardest working wardrobe pieces you will ever own. With a throw-on-and-go appeal, a midi dress needs minimal styling making it perfect for everything from those busy mornings and nothing-to-wear days, to important summer occasions. Comfy enough to lounge around in yet smart enough to be dressed up for the evening, there is no occasion too smart, too casual or with too many moving parts that the midi dress can’t conquer. Stick to classic prints and colours, such as florals or dots, or go all-in with colour-pop pieces that transcend the murky skies and make a statement wherever they’re worn. So, whether you’re headed to the office or to dinner, these dresses will take you from sunrise to sunset with ease.

Denim

Reliable; timeless; staple denim is a fabric that has proved itself worthy of pairing with almost any piece and any season. And because it’s durable but breathable, it’s an easy go-to when pulling together your September looks. Swap a floatier floral piece for a denim dress to give it a more autumnal edge, swap shorts for a pair of jeans or throw a denim jacket over your shoulders to show a warmer weather look who’s boss.

Trousers

Trousers aren’t strictly transitional; a linen pair is a steadfast summer essential and thicker woolly styles have become a winter-wardrobe staple for the more adventurous sartorialist, but a high-waisted or flared pair of trousers, paired with a light vest top or cami is a fashion fix that will carry you through myriad style briefs, regardless of occasion and climate. Whether you’re heading into the office or out to meet friends for that last hurrah to rooftop drinks, the trouser-top combo is one that sails through both smart and casual scenarios, easily dressed up or down by changing footwear and accessories.

Light layers

Yes, we’re back to talking about layering, but for good reason. Nailing light layering helps to give your summer pieces more longevity, while adding tone, texture and, crucially, warmth to an outfit. A timeless cashmere jumper can take you from day-to-night with ease, while a thin wool cardigan means you can bundle yourself up without breaking any style covenants. It’s a look loved by A-listers and comfort-seekers the world over, and far from detract from the outfit’s centrepiece, it comfortably frames it.

Blazer

From the runway to the high street, this smart throw-on has, quite literally, been a trailblazer in the upper echelons of stylish society and has cemented itself as a must-have wardrobe hero that works from boardroom to bar. Whether you want to give a whole new meaning to the tried-and-tested jeans-and-tee combo by shrugging on a blazer of choice, or add a tomboy edge to a slip dress with an oversized style, cinched at the waist with a leather belt, the piece is an effortless shrug to the weather forecast and a doubling-down on good design instead.

Sleeveless knitwear

Sleeveless knitwear is the cheat sheet for all fashion editors, the equivalent of having your answers to a particularly tricky test written on the inside of your shirt cuff, because they transcend the seasons and elevate any look with both ease and comfort. The beauty of this unassuming garment may lie in the fact it’s a layerable piece that adds instant texture and preen to any outfit, and though once firmly in the domain of golfers, it’s now a look loved by supermodels and the sartorial savvy the world-over. It also means you can carry on draping yourself in more summery attire and simply whip out your sleeveless saviour whenever the wind picks up.

Loafers

Once reserved for preppy, academic style types, the humble loafer is more than just a comfortable, polished day-to-day shoe, they add a generous dose of worldly sophistication to your outfits; a vibe that you're versed in all the latest runway happenings and can often be seen at the coolest parties, even when invites are thin on the ground. And they’re our go-to transitional shoe for good reason too, given that they look contemporary when paired with ankle socks and trousers in the colder weather and give an androgynous edge to bare-legged, summer dress looks too. Plus, you can plod the pavements, or parks, in them for hours and still have your feet emerge sans blisters come evening.