If you have blond hair, you might need a toner if you have just bleached your hair and have the raw pigment left over, or if you have hard water that is depositing an orange or yellow tint in your hair. A toner is a wash of color that you add to your hair to neutralize the orange or yellow tint. It uses the opposite color on the color wheel to cancel it out, so your hair turns a more natural, pleasing color. Toners can also allow you to achieve a different shade of blond.
Look in a hairstyle magazine to identify which specific shade of blond you want before you go to the salon or attempt to bleach your own hair.
Identify what stage of blond your hair is currently in. For example, if you hair is naturally golden or bleached to a deep golden color, your hair would be considered in "stage five." If you hair is a yellow color, you would be considered "stage six" and a very light yellow would be considered "stage seven."
Identify what brassy tone, if any, you currently have in your hair. If your light blond color has turned to an unpleasant yellow, choose a violet toner. If your hair has turned orange, choose a toner in a blue shade. Refer to the Resources below for the hair color wheel, which details more toner shades.
Keep your complexion in mind. Some toners will bring out a cooler tone in your blond hair, while others will deposit a warm, golden tone. If you have a very light complexion with light eyes and fair skin, warm up your skin tone by choosing a toner with gold or red in it. Neutralize a reddish complexion by choosing a cool beige or ash toner.