Where: Hyde Park
Joanne Black Style: Sharon Wauchob dress with Arthur & Fox tux jacket, Donna Karan sandals, a vintage bracelet, a belt by Martin Margiela and hair and manicure by Fred Gielly’s salon.

Summer parties don’t get much better – or more stylish – than the Serpentine’s annual soirée. Set in Hyde Park around the gallery’s latest pavillion – designed this year by leading Japanese architects Kazuyo Sejima and Ryue Nishizawa – this is the summer event to which everyone wants an invite.

After a few weeks of brilliant blue skies, I was even expecting the sun to put in an appearance. But it didn’t take long to realise I’d have to rely on the other guests to add a splash of colour to proceedings. And with around 1,000 outfits to admire, I wasn’t disappointed. The Serpentine attracts such an eclectic audience that it was never going to difficult to spot some stunning stand-out – and often daring – pieces. With everything from Rubinacci to Topshop on display, it felt at times like I was window-shopping rather than sipping wine in one the city’s Royal parks.

Thandie Newton looked fantastic in a multi-coloured tie-dye dress and skinny gold belt with cut-away ankle shoes and a blue leopard-print clutch; Daria Zhukova wore a stunning cream Alaia dress and belt with funky gladiator shoes, and Erin O’Connor opted for a spruce green Grecian-style Donna Karen dress, which really complemented her height and body shape. But it was rapper Pharrell Williams who stole the show with his equestrian-style outfit – complete with a white polo shirt, trimmed beige jacket (and matching hat) and blue jeans tucked into brown riding boots. Even without the horse, he pulled it off.

By the end of the evening, I was actually glad the sun chose not to show up. It meant I got to enjoy model Rosie Huntington-Whiteley’s cropped jacket from Topshop – that worked well with her violet maxi dress – and Luca Rubinacci’s fab slipper shoes, which he told me are too hot for Milan but perfect for London.

My only regret is that I didn’t get the chance to ask Tim Jeffries how he still doesn’t look a day over 40. I certainly need to find out his secret – and I’m positive the answer doesn’t lie in my current face cream!