Thou shalt not subject hair to more than two chemical processes.
"Any more is too damaging," says Sharon Dorram-Krause, head colorist at the John Frieda Salon in New York City. "You can do single process and highlights, but only if your hair isn't chemically straightened or permed." James Harris, master stylist for ethnic haircare brand Mizani, tells women with relaxed hair to use only cream-based permanent dyes, which have more conditioners than gels or liquids.

Thou shalt relate to thy skin tone.
Skin that has yellow undertones may look jaundiced next to hair that's too pale; deeper hues, on the other hand, can impart a beautiful golden cast. But rich browns won't do any favors for ruddier skin. "A dark color makes a bull's-eye around red areas," says Renée Patronik, colorist at Serge Normant for John Frieda in New York City and consultant for L'Oréal. Instead, lighten up with caramel or tawny brown highlights.

Honor thy childhood color.
When in doubt, peruse old family albums. "Stay close to the color you had when you were young," says Rita Hazan of the Rita Hazan Salon in New York City. "It will always be the most flattering on you."

Thou shalt lighten slowly.
If you plan to reclaim a towheaded youth, however, don't rush in. "Even at the salon, your hair will lighten only so much at one time—push it too far and it turns orangey," says Hazan. "Do a little every month, so you can control the brassiness."

Remember Thy Brows.
Never match your brows to a new haircolor, but consider making them a touch lighter or warmer. "The whole eye area can look younger and softer," says Bumble and Bumble color director Victoria Hunter.


From A Lesson Before Dyeing in the November 2005 issue of O, The Oprah Magazine.