The seven items you must have in your holiday capsule wardrobe - including the £25 must buy from Sienna Miller's M&S collection

Before we go any further, full disclosure: I want to look good on holiday but I’m no longer prepared to risk suncream leaking on to my best summer dress (so I leave that at home), or to pack shoes I can’t walk in all day.

And I’m not buying anything just to wear on a two-week break.

Twenty-five years ago I’d have stuffed all my favourite summer clothes in a suitcase and spent a month’s salary on a crochet cover-up, but now I know better.

I want to skip through an airport with carry-on luggage, which means refining that holiday wardrobe down to the bare minimum — seven can’t-go-wrong items — plus a couple of You Never Knows, for fun...

1. A pop-over day dress

It doesn’t have to be a pop-over — V-neck, loose fit, no buttons or zips or belt — but it has to be easy, breezy and ideally midi with three-quarter sleeves, because coverage in the sun when you can’t get out of it is what keeps you cool.

Sunny chic: Presenter Holly Willoughby shows black can be summery,

I’ve been wearing the same tenty, lightly-striped Zara dress for years — and it does the job perfectly. For something in a similar vein Hush does a lightweight maxi in petrol blue (£79, hush-uk.com). John Lewis has a faintly batik look, blue-on-white spot print, linen blend dress (£75, johnlewis.com).

Or, for something extra holiday floaty, there’s Aspiga’s Mykonos dress which now comes in maxi and midi length (£115, aspiga.com).

You’re better off with a plain colour or a geometric print — it looks cooler and they’re easily dressed up for night with some bold inexpensive jewellery. Try Zara for resin coral-effect necklaces or packs of beads and silk necklaces (£22.99, zara.com) and Mango for great shell earrings (mango.com).

2. Cushioned sandals

You’re travelling in the shoes you’re wearing for tramping the cobbles and to the beach. If you’re still looking for these, try Marks & Spencers’ suede footbed sliders in tan (£29.50, marksand spencer.com) or its flatform thongs in black (£35).

Otherwise, thanks to the current vogue for flat smart artisanal sandals to wear with everything, the cushioned elegant sandal is the only choice if you want an evening pair.

There are endless variations out there, but my favourites include Hush’s Thea footbed sandal (£99), and Me+Em’s T-bar sandals (£195, meand em.com) in gold or tan. They add elegance and make old holiday clothes look new.

If you really want some heel height — and why not — then there’s no substitute for a rope wedge on holiday. Try Hobbs’s ankle-strap espadrilles in cilantro green (£110, johnlewis.com).

3. Cool black trousers

They’re elastic-waisted for extra comfort in the heat, soft, light and wide so you can wear them day or evening. Boden does a cropped pair in doublecloth (£60, boden.co.uk) and Mango does a good longer style (£35.99, shop.mango.com). The beauty of these is they look great with a T shirt, a linen shirt or bright top, or you can double up with a black top to make a summery jumpsuit.

For something extra holiday floaty, there’s Aspiga’s Mykonos dress (pictured) which now comes in maxi and midi length (£115, aspiga.com)

4. The Little Black (Summer) Dress

This is the one you’ll wear after sundown, though it works in the day, too. It might have a more defined bodice, some pretty detail, maybe a ruffle hem, but it’s still simple and effortless. The Clarice cotton midi dress by Hush (£89) is a classic — an A-line-cut with a fabric tie belt that switches it up for evening.

Or, for those who have been busy with the weights, Nobody’s Child at Marks & Spencer does a sleeveless midaxi in a lightweight linen mix with a flattering deep V‑neck and fitted bodice (£79). There’s a black dress to suit everyone this summer. I gave up counting when I got to 50 on the M&S website.

5. An unexpected extra in a bold print

The pretty burgundy on white block print sarong skirt from the new Sienna Miller collection for Marks & Spencer (£25) — if it hasn’t already sold out — is a no-brainer for the holiday pile, even if it breaks the ‘no buying specially for holidays’ rule. With a white T, or over a swimsuit, we can pretend to be Sienna for a nanosecond. Sigh.

6. A wild bag

Mango’s net bag in orange trimmed with silver beads (£79.99) will put a rocket in everything you wear.

7. A pretty scarf

Last but not least, a wrap or scarf to sling on in the evening — try Aspiga or Nrby Clothing (nrbyclothing.com) — will keep you warm in a breeze and add a dash of colour. I’d take two.