Emma Stone‘s red-carpet updos, Olivia Wilde‘s boho waves, Cara Delevingne‘s tousled bends, or Zoe Saldana‘s polished blowouts, you have Mara Roszak to thank for that. The Los Angeles-based stylist and Laurel Canyon native is a master of arguably the most coveted aesthetic in hair: beachy, artfully disheveled California cool.