In general, apply your root touch-up “only where the regrowth is visible,” like the part and hairline, Aral advises. “Do not try to color your whole head, as this can cause overlapping or missed spots, uneven color, and blotchiness,” Ikeda says.
Also, consider the type of product you’re using: “With a spray, aim the nozzle towards the part almost parallel to the top of the head and spray once or twice, starting from the front and moving back,” Ikeda advises. “With powder forms, start applying at the front of the head and move back along the part.” When finished, lightly brush through hair to blend.
Wash your hands after application if any product has transferred. “Keep in mind that temporary root touch-ups can transfer or bleed if exposed to water or after a workout and will wash away with your next shampoo,” Aral notes.
