Because red hair can change so quickly, it's a good idea to not wash your hair everyday. "Dry shampoos are amazing for in between washes," says Stephanie Brown, master colorist at IGK Soho. She's a fan of this dry shampoo because it doesn't leave residue, "which can mute vibrant reds," she says.
If you have to wet your hair in between shampoos, use products that are good for in-between washes, like this apple cider vinegar rinse, suggests Brown. "These [kinds of products] help you feel clean but without stripping the color," says Brown. She also advises using the coolest water you can stand because hot water will strip color.
Brown likes this hair mask, which nourishes strands and also revitalizes hair that's dulled. If they don't have the red color you want (copper is shown here), you can mix two shades together to create one that works for you.