Mix up equal parts beige-blond color and five-volume color developer in a color bottle. Squirt it on your clean, dry hair and wait about 15 minutes to tone the brass out of your hair. Rinse with warm water. Follow up with purple color-enhancing shampoo and conditioner. Tone your hair after each highlight and in between highlights anytime the brass becomes too much.
Use purple color-enhancing shampoo and conditioner on your hair weekly. Lather it up the way you would with any shampoo. Comb the conditioner through your hair to the ends with your fingers or a wide-toothed comb, wait five minutes and rinse with cool water.
Consider your water. If the brass gets worse over time despite your best efforts, the culprit is likely your water. Soften your water with a water-softening system or a filter that screws right on your shower head. If you have well water or a rain-water collection system, do not wash your hair in it. Purchase distilled water to keep mineral deposits from collecting on your hair and turning it orange.