WILL REPEAT DYEING DAMAGE MY HAIR?  "Not if you use a hydrating formula and don't color your hair toooften," says Kyle White, colorist at the Oscar Blandi Salon in NYC.  To color at home, choose a haircolor kit that contains conditioners such as avocado oil, or apply a moisturizing and shine-enhancing gloss (found in salons or at drugstores) between touch-ups.  Also, keep in mind that going darker disrupts the cuticle less drastically than bleach-based highlights do, therefore inflicting less harm.