Sleeping in a loose bun prevents your hair from getting messed up during the night. It also helps against tangling and frizziness because your hair isn’t rubbing against a pillowcase all night. Bonus: this can add a little volume to your hair. Add some curl or texture cream to damp hair, throw it in a topknot and go to sleep. When you wake up in the morning, you’ll have loose waves. Easiest hairstyle ever.