The Girl: French actress and singer; daughter of Jane Birkin.
The Trick: Oscillate between nonchalant "I'm with the band" pieces (skinny jeans, military jackets) and absurdly polished eveningwear (pencil skirts, chiffon blouses). But either way, always top each look with beachy hair to add that undone cool element. Sooooo French.
Click through to shop her look.
Photos via French Select, Getty Images