Who says dressing up has to be a highbrow activity? This week the stars were all about keeping fashion fun. While Rihanna wasn't afraid to take a spill in skis, Lupita Nyong'o spread her wings with a butterfly headpiece.
After all, though great style is serious business, it's nice to see Hollywood still has a sense of humor. See this week's best photos, and don't forget to share the love and follow POPSUGAR Fashion on Instagram, Facebook, and Twitter!