We think before we buy these days, right? And so we damn well should. Shopping should not be a pastime. Style is eternal, not disposable. Each piece that has made the cut into my edit of March treasures has earned its place. A pair of £10 socks that are an instant wardrobe update. The ideal new-season nail polish for £8.

And you don’t have to buy anything at all for it to be worth having a look at my list. See below for my thoughts on what makes a boho blouse cool rather than twee, and a tipoff about the return of the brooch. That’s what I love about fashion: you don’t have to buy it to buy into it. But whatever you do, don’t buy anything until you read this.

This shortlist of items are covered in a new column for the Filter.

The brooch is back

Yves Saint Laurent tricolour logo brooch
£49 at Vestiaire Collective

Yves Saint Laurent gold and crystal brooch
£99 at Hewi

The favoured accessory of minor royals and secondary-school art teachers is making a fashion comeback. The return of the brooch was my number one takeaway from a recent trip to New York fashion week, where the chicest show-goers all had something fancy pinned to their coat lapel or beanie. I don’t think many people are on to this yet, which means that now is the time to pounce on a bargain vintage brooch before they get in on the act. Why wait for the high street to catch up (although it will, mark my words) when you can source something original and preloved? I have my eye on two fabulous Saint Laurent brooches: a tricolour logo brooch on Vestiaire Collective, and a sleek gold-and-crystal number, £99 on in-the-know resale site Hewi, which stands for Hardly Ever Worn It.

The socks I am obsessed with

Bow socks
£10 at Calzedonia

It is impossible to overstate the importance of socks in fashion right now. These are adorable. If you wear them with jeans, you flash a bow now and again, but they come into their own with a party dress. They come in white with black bows or all black, but the pink-on-pink is giving Simone Rocha, for a tenner.

The perfect coffee-break manicure

Turks And Caicos Beach nail polish
£8 at Nails Inc
£8 at Amazon

Cappuccino-coloured nails look great with everything. This polish shade is subtle enough that if – like me – you’re not exactly a dab hand on the DIY, a few application wobbles won’t show.

A cool boho blouse

Cheesecloth blouse
£75 at Me+Em

There’s a fine line between boho and trad-wife, and it feels important to stay on the right side of history here. A boho-style blouse is a useful buy because it works for daytime but can be easily dressed up with a kitten heel and some nice jewellery when you’re going out for dinner and want to make a bit of an effort. But I’ve learned the hard way that what feels charming and feminine in the heady atmosphere of a store changing room can seem costumey and twee in the cold light of day. Me+Em is never cheap, but its clothes are thoughtfully designed and beautifully made, and always walk the right line in looking feminine but not cloying. This cheesecloth blouse has an elevated neckline that gives a pop of interest poking out under a crew-neck knit, so it’s great for layering and will come into its own in summer. The peach sorbet shade is delicious, but it also comes in white and two alternative blues.

The pilates pump is the new ballerina flat

Anyday Hennriette Point
£49 at John Lewis

Ballerina flats never quite live up to their elegant name, on me. Something about the way a ballerina flat leaves the top part of my foot flat lacks grace, visually. And yes, I know we have bigger things to worry about in the world right now, but it still bugs me. I’ve found the solution in a new genre of ballerina/Mary-Jane hybrids, with a strap across the top – like the socks people wear at pilates, hence the name. Looks much more pleasing, and is more comfortable, being more secure to the foot. This John Lewis pair, with a ruched strap and pointed toe, look very classy for the price.

What’s hot – and what’s most definitely not – this week

Going up

Builder’s bums | See (or try to unsee) Zoë Kravitz’s bum-baring dress at Vanity Fair’s Oscars party and Diesel’s bumster jeans.

Cobblestone | Not just for medieval towns. Interior designers are championing the uneven stones as a way to add old-world touch to new builds.

Static | The frizzy ponytails at the Prada has left us wondering if they rubbed the models’ hair with balloons backstage?

Going down

Walk-in wardrobes | Carrie Bradshaw would weep with envy. The 1% are constructing “shouses” – shop houses – to store and display their vast fleets of cars, antique boats and designer clothing, complete with built-in bars and fireplaces. *Cries in underbed storage boxes*.

Oura rings | Cynthia Erivo’s manicure for the Oscars included a tiny hand-painted Cartier clock face. Way better than a sleep tracker.

Bed rotting | SomeAmericans are celebrating getting into university by throwing a “bed party”, featuring balloons and duvet sets with the colours of their future alma mater alongside branded merch. We’d take a lie-in.