"Kérastase is a fabulous product for wigs," she said. "We were washing them all with the Kérastase Résistance Bain Extentioniste Shampoo For Long Hair ($33) because all the wigs were coloured. That's how you make the wigs look real. For wigs with natural hair, they don't dye them with ordinary hair colour; they use fabric colour, like Dylon. So the Kérastase conditioners and masks were key to making them look good."