Bad hair days — we've all been there. Lucky for you, this season's hottest hair accessory is the headscarf, the simplest solution for quick and easy hairstyles since the bobby pin. The best part: You don't have to go out and buy a ton of headscarves (unless you want to). Chances are, you already have some sort of scarf, bandana or wrap that you can use to hide your frizzies, add polish to your updo or give your outfit a retro vibe.