My five summer suitcase essentials: How to dress like a grown-up with Shane Watson

Finally, I think I’ve cracked it. I still have a laundry bag groaning with products even though I only use two. And my handbag is a lucky dip: I haven’t seen it in over a year.

But when it comes to style, I’ve nailed the all-you-need-for-a-week holiday wardrobe in five steps — and that means happier getaways and more satisfying shopping.

If you’re anything like me, you usually shop wisely. Then every now and then you get off track, telling yourself that if you don’t wear the Lurex halterneck at home, it will be perfect for a vacation.

Well, that will never happen again. And no more stuffing the suitcase with shoes (two or three pairs are enough – a comfortable flat sandal; something more elevated, such as a cork wedge; and slippers).

No litters of you never know bikinis, just the flattering bathing suit and the extra comfortable one that you can wear all day. (If you don’t already have the above, try Boden.)

Sophie, Countess of Wessex, paired her tiered floral maxi skirt with platform sandals

I don’t wear shorts or T-shirts anymore because I look and feel cooler in an A-line dress, and a decent cover-up is better than fussy unflattering sarongs and long, linen shirts.

I’m not saying everything I pack is a multipurpose bullseye, just that my days of being all-everything-and-hoping-for-the-best are behind me. So, here goes. You won’t look back.

1. A beach blanket

The right cover-up will look good on the beach, at lunchtime and while strolling through the local village. It is light but not sheer, short or caftan-like. The style that works for me is a longish pop-over (as they call it in the US), with a V-neckline, no buttons, a tie belt and long sleeves.

Mine is from Nrby, and the label’s current offering, the Chrissie maxi (£170, nrbyclothing.com), is similar. It gives you the coverage you need to keep the sun out and walk around, and it’s dressy enough to wear to lunch in the garden at home.

2. The all-rounder dress

Last year’s do-it-all dress was the tent dress – wide, layered and long or short. You won’t get any style points for wearing it this year, but you might want the prettier version.

Nrby’s Jaclyn dress in royal blue cotton (£99, nrbyclothing.com) is a slimmer A-line with fringe at the elbow sleeves.

If you want to take two with you on vacation – and why not? — M&S has an ivory V-neck cotton midi with a black print (£49.50, marksandspencer.com) looking fresh for the day, with black sandals.

Then you need something that’s easy to pack and a cinch to dial into the evening, like one of Me+Em’s cheesecloth dresses (from £150, meandem.com). Cheesecloth is light, soft and pre-wrinkled — no ironing required — so it’s perfect for holidays.

NB: You don’t want to bring a silk dress: it doesn’t pack well and you feel overdressed. It’s much better to embellish something simple with bold, inexpensive jewelry.

Swedish model Elsa Hosk wears a short leather jacket with her belted maxi skirt

Brazilian model Alessandra Ambrosio looks fresh in a summery maxi skirt and matching crop top

3. A jumpsuit

Mosquitoes and a cool ocean breeze (especially the former) have made me a big fan of leg coverings at night, but just bringing stretchy silky pants and top makes me feel like I’ve gone to the sloppy side .

The solution is a linen or cheesecloth jumpsuit, such as Wyse’s woodblock print, a wide-leg cap sleeve (£195, wyselondon.com) or a full-length skirt. The jumpsuit becomes a chic going-out look when paired with cork wedge mules (now £59, dunelondon.com),

I’m also still a fan of the mid-heel espadrille, wedge heel and ankle strap. These high rope soles are perfect for trudging through cobbled streets during cocktail hours, and with an orange toe cap and pink strap (£69, johnlewis.com) they’re fun too.

4. A maxi skirt

I love maxi dresses and have tried endlessly to wear them on vacation, but always feel like a diplomat’s wife circa 1976 – too stiff and dressy. For Mamma Mia!-esque vibes, the answer is a maxi skirt.

Zara has a long paneled skirt in various block prints (£32.99, zara.com) with a smocked waist. Don’t let this put you off, it means you can wear it high or on your hips with a smocked crinkle cotton top (£79, nrbyclothing.com).

5. A cardigan/shawl

I’ll take a cashmere shawl (£160, toast.st), but a cardigan in a bright color also works for draping or wearing (£19.50, marksandspencer.com). Then all you need is a denim jacket.