Love Eva Longoria's intense tresses? Achieving a deep brown is no easy feat. Find a formula that's semipermanent (it washes out in 8 to 12 shampoos) if you just want to pump up your color or are less than 25 percent gray—your grays will look like natural highlights. If you have a higher percentage of gray, look for a demipermanent shade, which lasts through 28 shampoos and blends away gray. If you are more than 50 percent gray, and go for a permanent formula to achieve complete coverage. Avoid such an intense shade if your skin is very fair. Instead, look for soft, light-brown shades, because intensely dark hues might prove too much of a contrast against a pale complexion.
Steal Eva's shade: Age Beautiful Liqui-Creme hair color in Deepest Brown, $6; sallybeauty.com