The former 'Hills' star turned fashion designer loves how the 'Great Gatsby' actress dresses as she always looks ''flawless''.
She said: ''A star whose style I love is Carey Mulligan. She just always looks flawless and adorable.''
Meanwhile, Lauren admitted one of the best things about being famous is being able to afford nice clothes.
She told America's OK! magazine: ''Before I was a celebrity I never thought I'd own expensive clothes. I had a very limited clothing budget growing up which is great because I didn't get spoiled.
''But I love that now I can buy whatever I want.''
The blonde favours a natural look and hardly ever wears eye shadow because she thinks heavy make-up doesn't suit her.
Lauren previously revealed: ''Winged eye liner is my go to because I actually don't look good with a lot of dark shadow. It makes my eyes look sunken in. The thing to remember is that you're wearing the make-up, you can't let it wear you.
''Make-up should enhance what you have. You don't want to look unrecognisable when you wash your face at the end of the day.''
Many ticket-holders couldn't get into the O2 Arena show on Tuesday night (September 19th) because they didn't bring photo ID to match their booking.
An album re-release, a new song and a documentary mark the singer's legacy this year.
The actor plays the titular hero in the forthcoming adaptation.