S.B.
Do you have a facebook page for your business? You could spread the word that way and offer special deals when you know you are going to be slow. Or offer a new customer discount. Give people an incentive to refer clients to you--get some business cards printed on Vistaprints (which is cheap or sometimes free) with your info and a line that says "referred by" If someone comes in with the card, they get a "free shampoo" or something and the person who referred them gets something free too. Good luck!