Consider the lighting. "If you're going to be outdoors, pick a softer or sheerer shade," says Rachel Lockhart, owner of Rachel's Makeup Studio, in Boston. "For evening, go bolder, so your features stand out."
Avoid deep reds if you have thin lips. They tend to make lips look smaller.
Experiment with intense shades if you have strong coloring. "Natural contrast gives you more options," says Jill Morton, head of ColorCom, a consultation agency in Honolulu, says of those with exaggerated natural coloring (for example, paper-white skin, black hair, and blue eyes).
Don't play up your eyes. "Pair red lipstick with the lightest possible eye makeup," says lipstick designer Poppy King. A little mascara and beige shadow will do.
Don't toss a red lipstick in a shade that doesn't work. "Top it with a gold gloss to warm and soften it, or add a pink gloss to take it to the bluer side," says makeup artist Maria Verel.
Coordinate your look. Dot a little smudge of the lipstick on the apples of your cheeks, then blend it with your fingers.
Be precise. That means whether you're using a brush or applying lipstick straight from the tube. "Red lipstick should never be applied casually in the back of a taxi," says Verel.
Don't use red lip liner. If it doesn't match your lipstick perfectly (and odds are it won't), you'll end up with a two-tone effect. If you like using liner, find a shade that's close to your natural lip color and use it to outline your lips.
Prevent "bleeding." Apply a little concealer around the border of your mouth.
Avoid getting lipstick on your teeth. After applying, put your finger in your mouth, purse your lips around it, then slowly pull it out to remove excess color.