Suki Waterhouse uses make-up as "armour".
The 25-year-old model thinks cosmetics are a great "tool" because they can help give a sense of confidence, make someone stand out, or fade into the background.
She said: "As I've grown up it's really about context - like what you need from that day.
"Sometimes I want to disappear and melt into the background and wear a hood and no make-up.
"And then sometimes, like if you ask for a raise, you want a shield of make-up on - it really is armour.
"Make-up is a tool, at our disposition. We're the captain of the make-up ship."
Suki has been friends with fellow model Georgia May Jagger since her schooldays, and credits her pal's mother, Texan supermodel Jerry Hall, for teaching them a lot about beauty and modelling basics.
Discussing her first experiences with beauty with Miss Vogue magazine, she said: "I remember being obsessed with sky-blue nail polish - Hard Candy and stuff like that. I also was obsessed with lightning bolts because of Harry Potter and then Bowie.
"I learned some good basics from my mum. She's not someone who cakes it on, she's just really naturally gorgeous.
"And then I learned a lot from my friend Georgia May Jagger - we'd be around her mum and she'd teach us how to catwalk. I've always been kind of fascinated by that long blonde hair and big red lips I'd see on Jerry and Georgia."
But Suki admitted it could be tricky to experiment with the "loud" looks she appreciated, because of strict rules at school.
She added: "And then I'd look up to Britney Spears and the Spice Girls, so it was all very loud make-up and fashion. At school the goal was not getting in trouble for wearing make-up."