Fashion: Wake up to sleepy chic

Looking like we've slept in our clothes is a look we rarely aspire to, yet somehow often achieve. Good news, then, that fashion has decreed that nightwear is the new daywear this summer. And you don't even have to don a nocturnal ensemble as glitzy as the sequinned bed jacket and silk shorts combo that New York designer Derek Lam sent his model down the runway in to look the part.

The slouchy, classic pyjama is proving to be this season's most stylish option, as designers such as John Galliano revive a look introduced in the 1920s by Coco Chanel for casual "lounging" at home or the beach, and which was later championed by the Studio 54 crowd as being perfect for after dark, even if you weren't going to bed. Now it is back as the only outfit that will take you from bed to bar with the addition of a bangle here and a platform there.

In reality, however, it's hard to imagine being able to perch on a cocktail stool — let alone get eight hours shuteye – in Preen's silk drawstring numbers or Stella McCartney's dusky blue PJs without ending up with more creases than the PM's forehead.

And therein lies the inevitable snag. The tailoring may be deconstructed but this is no low-maintenance look. Luxe fabrics such as heavy silks and sheer chiffons add the glamour factor and, as states ancient fashion lore, the more relaxed the clothes, the more rigorous the grooming demands – immaculate hair, skin and nails are all essential if this is to shout "couture" rather than "care-in-the-community".

Phew. Just thinking about it is enough to make you want to go back to bed.