Over time, hairspray can build up on hair, which reduces its shine and bounce. Luckily you don't have to spend a lot of money on expensive products to remove hairspray buildup. You can use inexpensive products you probably have at home. These products are gentle, which is especially important for removing hairspray buildup from color-treated hair. Squirt 2 tbsp. of Dawn liquid soap into a small container. Add 2 tbsp. of baking soda to the liquid soap. Stir the mixture until well blended. Wet your hair thoroughly and rub the soap and soda mixture into your hair. Massage the mixture throughout your hair and scalp. Rinse your hair until the soap mixture is completely gone. Apply conditioner to your hair and rinse it out after you've massaged it in well. This is especially important for color-treated hair in order to prevent dryness.