When I was a teenager, there was one wardrobe item that was essential for a Saturday night out. I’m talking about the slip dress, that tiny piece of fabric with spaghetti style straps and a look that was distinctly more negligee than frock. I wore a pink short version the first time I met my husband, and used to actually buy vintage nighties to wear as dresses, sometimes grunge style with a t-shirt underneath, other times more glamorous with lots of faux pearls or diamante. Kate Moss was queen of the slip dress, and there was no-one cooler than Kate in the 90s. And although they’ve never really gone away…