As far as maintaining highlights, lowlights, and colored hair, don’t use color on bleached or highlighted hair, as it can be absorbed into the more porous hair that has already been treated, which will make the new color look uneven.
If your color is fading, try a semi-permanent to refresh your color. Semi-permanents darken hair and add warmth and shine. It will only last up to six washes but will revive your shine instantly. A color gloss will tone down greys and add warmth, but only lasts until the next month. Regular maintenance is the way forward to stronger, healthier hair. Cheaper shampoos can strip hair, leaving you with a faded color after a few weeks. Good-quality, color specific shampoos like Aquage Color Treatment shampoo are the key to long-lasting color.