Princess Eugenie makes styling halternecks look easy as she returns to current favourite frock with comfy kitten heel mules

There are some necklines I’m instantly drawn to and others - like halternecks - that I need a bit of inspiration to try on. When you’re not sure what to wear in the heat, the breezier a design the better, and halternecks often fit into this category.

The lack of sleeves is the most obvious plus point and this neckline also feels quite vintage and chic. Knowing how to style halternecks isn’t something I’m an expert in, so it was great to see Princess Eugenie showing how it's done.

As Global Ambassador for The Coral Collective, the King’s niece attended the exclusive opening of the Thirty Six For Coral art exhibition in France on 12th June. Just like many of us, she wasn’t afraid to re-wear a tried and tested combination for the event: her Rebecca Vallance orchid dress and Staud satin mules.

Shop Princess Eugenie's Dress

This was the same stylish combination Princess Eugenie wore to Chelsea Flower Show in May and I wouldn’t be surprised if the dress and slip-ons get another chance to shine this summer too. Although she often champions the best British clothing brands, Rebecca Vallance is an Australian designer whose pieces are also regularly worn by the royals.

Made from a linen blend, it has a collared neckline with structured lapels that give it a refined edge. The bodice is fitted and the midi-length skirt flares out into an elegant silhouette.

Running all over the white base is a pattern of electric blue orchids and vines that bring added brightness. Part of why I love the Princess’s frock so much is because it feels sophisticated, whereas some halterneck pieces can be a bit too revealing or beachy-casual.

Shop Mules

I can imagine this as a date night outfit, as well as something you could wear to a family BBQ or a garden party. When you’re looking for a halterneck dress, consider something that has a classic shape like fit-and-flare or A-line, and is generally neutral in colour.

The white background tone of Princess Eugenie’s dress balances the blue flowers and I’d recommend following a similar approach. If you choose a halterneck dress which is mainly black, white or a tone you wear consistently, you’ll always be able to find accessories that complement the outfit.

To make it slightly more relaxed the royal could have worn trainers but she went for camel satin heels from Straud. Kitten heeled mules were a clever pairing as they are comfortable and quick to slip on and off and yet look quite glamorous.

Princess Eugenie painted her toenails red and they were just visible through the peep-toe cut-out. The warm weather required a breathable outfit and she spoke at the launch of the exhibition, which coincided with the UN Oceans Conference.

Her Royal Highness is a member of the Thirty Six For Coral art committee and helped to shape the exhibition, which includes 36 original works from artists including Rocco Ritchie and Vik Muniz. The online auction is running until 22nd June and proceeds go to support coral reef protection and global restoration efforts.

Speaking to Marie Claire, Princess Eugenie described coral reefs as the "rainforest of the sea" that "support billions of human lives".

"Across the planet, coral reefs are in trouble. The loss of coral reefs could be the first functional climate extinction in our lifetime," she declared.