While do-it-yourself hair color is a great way to save some money, it can get very messy. Hair dye stains often need to be treated with a variety of cleaners, before they can be completely removed. Fortunately, many of the solutions for hair dye stains are regular household items. If you treat the stained area immediately, you are much more likely to be successful in completely removing the stain without repainting.
Immediately blot the dye before treating it. If you wait until the stain is dry, it seeps deeper into the layers of paint, making it harder to remove. Trying to rinse the dye off with water is likely to spread it. Using an old towel to blot is best, because it's far more absorbent than paper towel.
Mix 1/4 tbsp. of dish washing detergent in a cup of lukewarm water. Use a sponge and gently scrub the stained area. If the hair dye splattered a lot, try to stick to one small section at a time. Rubbing the sponge back and forth across a large area could spread the stain.
Treat remaining stains with a 3 percent hydrogen peroxide soaked cotton ball. Blot the stained area with the cotton ball and allow the area to try for 24 hours. This process can be repeated daily for two or three days. After two or three days the peroxide may start to have adverse effects on the wall so you may want to try an alternative.
Paint over the stain. If you live in an apartment complex, maintenance should provide you with paint free of charge. If you continue to try strong treatments on your walls, it will start to peel away the paint and you will have to paint regardless.