If you’re afraid to go bold for fear of using a color that clashes with your skin, Self says to look at your vein color. If your veins are green then go with colors that flatter the warmer skin tones, such as orange, pink, and red. If your veins are blue, then go with colors that match cooler skin like purple, mauve, and yellow (try OPI’s Need Glasses?). Greens tend to go with both, such as Nubar’s Greener (pictured at top right) or OPI’s Go on Green! nail lacquer.