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Light from above creates unflattering shadows. For the most shadow-free reflection, install bulbs on either side of your mirror, about five feet six inches from the floor and three feet apart. Or put a table lamp on a counter or dresser next to your mirror.

Cold, white light is harsh and can lead you to overcompensate with makeup. Look for bulbs with a warmer "color temperature" of about 3,000 kelvin (a unit of measure listed on the packaging).

A bright but not too powerful glow most closely mimics the intensity of natural light. An incandescent bulb should be 75 watts; in an LED bulb, go for 14 to 16 watts.

Get the Perfect Lighting When Traveling
"When I travel, I always pack a magnifying mirror with suction cups in my carry-on. Because in my experience, even at the nicest hotels there's never a makeup mirror with enough magnification. I like to apply makeup in daylight, since that gives the most natural-looking results. So once I'm settled in, I stick my little suction-cup mirror on a window at eye level, and presto—a trustworthy reflection!"—Val Monroe, O's Beauty Director

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