I cleanse, tone and moisturise religiously every morning and evening, she told me. So no sneaky wipes when you stumble in at 4am? No, they remind me of camping trips when I was 13!
Another thing she associates with being a teenager is using Rimmel products: They were always a staple in my make-up bag and my sisters when we were growing up. Fitting then to see that Rimmel have signed up a genuine fan and that Lily is now a face of Rimmel this season she is fronting their Stay Matte range.
I dont wear much make-up, but Ill almost always leave the house wearing a little powder and mascara [Lily is wearing Stay Matte Powder in 002 Pink Blossom, £3.99, and The Max Volume Flash Mascara in 003 Ultra Black, £6.49, both by Rimmel when we meet]. For evening, a red lip is quick and easy, or if I have time, Ill do a smoky eye.
Another way I like to do my eyes is to press some black eye shadow under the upper lash line, so it drops on to the bottom lash line. Its slightly messy but it looks really nice, says Lily. Its a tip she learnt from one of the many make-up artists shes worked with over the course of her seven-year career. Has she picked anything else up along the way?
I really like the way Pat McGrath applies eye make-up she uses her finger to really work it in to the sockets. And Val Garland always uses a fibre optic [synthetic] brush to apply foundation. You get a softer, smoother finish that way.
Her final tip? Dont over-pluck your eyebrows. Tidy them, yes, but thicker eyebrows look more attractive, whoever you are.
Find out more of Lilys beauty secrets in this months ELLE magazine.