"Batiste Dry Shampoo in Fresh (£2) is the perfect in-between dry shampoo. It's affordable (which is a good thing, because you'll blow through bottle after bottle), but works better than supercheap drugstore brands. It feels light on your hair and smells great and doesn't leave a weird buildup after using it for a few days. Just last week I went without shampooing for an alarming five days, and guess what? No one could tell." — Mandy Harris, managing editor