Turn on the shower when your timer goes off, indicating the peroxide mix has finished processing. If you don't use a timer, you run the serious risk of leaving the dye in for too long and stripping your mane of color and health.
Rinse the dye out in the shower until the water runs clear. If you see any streaks of dye in the water running off you, keep rinsing. If you're worried, give things a couple more minutes.
Shampoo your hair with a quarter-sized dollop of shampoo for color-treated hair. Sudsing up helps you rinse out any last peroxide molecules that are trapped in your locks.
Rinse again until all the suds are gone.
Condition your mane with a rich conditioner for color-treated hair. Using hair dye strips moisture from your locks, so working overtime to restore it helps maintain hair health.
Before you leave the bathroom, take a few minutes to make sure all the dye was rinsed off your shower floor and walls and your sink, so you don't stain fixtures.