If you're still trying to work that blowout from last Saturday night, relax. A skinny headband—and a messy updo—can take not-so-clean hair into a whole new stylish realm. "Hair accessories say ' I made an effort, but not too much,' " says L.A. stylist Lona Vigi. No accessories on hand? Mine your jewelry box. Refashion a necklace into a headband (just pin it in place), or add a sparkly brooch to the side of an updo. Insta-chic!