8. Drybar Prep Rally Prime & Prep Detangler
Thin, weak hair has the tendency to tangle — and badly. Help keep your hair under control by using this prep spray before you style your locks. It's formulated with biotin and vitamin B, and not only does it detangle, but it also protects hair from heat.

Drybar Prep Rally Prime & Prep Detangler, $23, Sephora