So far, I've only used Sun-In three times, applying to the bottom half of my hair only (and somewhat randomly to get natural-looking highlights here and there) with the hope of eventually creating an ombre-like effect. All three times, I used a blow dryer to 'activate' it. Hearing that its takes most people with darker hair a good month to get it to lighten to a light brown, almost dark blonde, I'm expecting to reach my desired results after about 6-10 more uses.
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