Navy is softer than black and more polished than gray. Khaite's wool Celton blazer, Rùadh's Stewart blazer, Loro Piana's pinstriped blazer and Veronica Beard's houndstooth Molyneux blazer are four different takes.

For a relaxed morning, wear the blazer over a striped shirt and jeans. Jamie Haller's ivory striped poplin shirt and Citizens of Humanity's Winslow boyfriend jeans are an easy base. Saint Laurent's pony hair Le 5 à 7 Bea tote and Bottega Veneta's burgundy Silenzio loafers add polish.

At work, go tonal with gray trousers and a fine knit. Khaite's gray August flannel trousers and Ami Paris' navy merino sweater look sharp under the blazer. Neous' black leather pumps and The Row's dark brown Cecily tote keep it professional.

For drinks, swap the trousers for a satin skirt. Dôen's sage green lace-trimmed Elowette skirt and Carine Gilson's black silk cami look lovely under navy. Jude's black satin Kiss pumps and Carolina Herrera's leopard jacquard clutch finish it.

On the weekend, the blazer turns a T-shirt into an outfit. Toteme's white Garderob T-shirt and Maison Margiela's cream Replica sneakers are relaxed, while Brunello Cucinelli's tan suede cap and Gucci's beige Jackie shoulder bag add a little luxury.

A good blazer should work as hard as your favourite jeans. If you take one thing away, let it be that navy is easier to mix than black, pairing well with denim, gray, burgundy and even sage green. Choose a single-breasted style with a little room in the shoulder so you can layer a knit underneath. We would skip very cropped or heavily structured versions if you want to wear it every day. Push the sleeves up with a tee for the weekend and wear it buttoned with trousers for work. The same jacket carries all four looks here.