So, Kate Thinslet, how did you do it?

Kate Winslet scored a critical bull's eye on the red carpet on Sunday night when she stepped out for the premiere of her latest film, Finding Neverland.

Gone were the carping criticisms of old - everyone loved That Dress and Kate made the front pages of almost all the papers the next day.

But what exactly was it that made Kate look so fabulous? And what can we learn from her example, if only to up our own va-va-voom at the next dinner party?

First off, she kept it simple. Cheryl Konteh, my senior fashion editor and Kate's personal stylist, says she encouraged the 29-year-old actress to choose a style "that she knows suits her, a classic silhouette".

"Kate is a British size 10 and has got a beautiful womanly figure; this dress celebrates the positive attributes of her body," says Ben de Lisi, who designed the one-off gown. "She isn't the kind of woman who needs to call attention to herself, so when designing the dress I knew to keep it very simple."

The colour - described by de Lisi as aqua - is a great match for a blue-eyed blonde. It's not cutting-edge fashion - like green or purple, say - but it is flattering. Too many actresses take the high fashion route, and wonder why they don't look good in photos the next day.

Made of silk crepe with a boned corset, de Lisi's dress was designed to look sleek but work hard, too. "It's bias cut, so it's forgiving in the right places, and it won't crease," the designer explains. Plus, says Konteh, "the halter-neck shows off Kate's shoulders, but it doesn't make her look at all bulky."

The floor-length gown certainly highlights her slim waist. Whether or not she's lost weight doesn't actually matter; she looks sleek, toned and lightly tanned (which has a slimming effect anyway). Her make-up (by renowned make-up artist Val Garland) is grown-up without being overly dramatic. And her hair (by Nicola Clarke) is the best it's ever been: a soft, natural blonde in a style that's "done" but doesn't make her look old beyond her years.

But I think there are a couple of extra ingredients here, too, that didn't come out of a wardrobe. Kate has benefited from past bad experiences on the red carpet and now knows how to present herself - standing tall, with a wide smile. And, most importantly, with her new baby and husband, she's feeling happy on the inside ...