Brassy is a term that hair care professionals often use to describe an orange tone that hair takes on when it has not been dyed correctly. Brassy hair is a common problem that happens most often to brunettes who lighten their hair blonde: often the hair dye is not left long enough on the hair and orange, a shade that brown hair passes through before it gets to blonde. You should try neutralising the hair colour at home before seeing a professional.
Mix 1/4 cup of toner with equal parts bleach in a small plastic bowl. According to the experts at Hairfinder.com, the bleach will prevent a further lift, but allow the colour to deposit.
Dip the brush into the toner and bleach concoction and apply directly to the brassy hair where there is new growth. Let the mixture set for 10 minutes.
Comb the dye that you've already applied to your hair, throughout the rest of your hair length. Distribute it evenly. Leave on for five minutes.
Wash and condition your hair with products for coloured or chemically treated hair.
Consider using a "debrassing" or "brightening" shampoo or conditioner if colouring your own hair makes you nervous. According to the haircare professionals at Hairfinder.com, "These shampoos use a blue-dye base which counteracts the orange results commonly found in lightened hair. Because these shampoos don't permanently alter the colour of the hair, they are usually very safe to use, but may be less effective in some cases where the orange colour results are very bright."