Bobbi Brown is obsessed with concealer. It's her desert island beauty product (providing there's another person or a mirror). "A good concealer is the secret of the universe," says Brown. "When you find the right one it can instantly brighten your face and make you look wide awake."
For a concealer to do its job, it needs to disguise whatever it is you're trying to conceal, not draw attention to it. A blemish caked in concealer looks worse, not better, and that's the first rule of concealer: never use it to cover blemishes. "Concealer is designed to be one or two shades lighter than your skin tone," Brown says, "so this will only draw attention to your blemish." Concealer should only ever be used to even out skin tone, not radically alter it, masking under eye circles, say. "After covering up under eye circles, you'll often find that you don't need as much foundation as you thought you did," she adds.
"Women with dark skin should use concealer and powder that is yellow-based so as not to make the eye area look ashy," says Brown. "Your concealer should be just one shade lighter than your skin and your foundation." Avoid concealers that are too light, or have pink or white tones (according to Brown, "The exception would be some Middle Eastern women who have purple-ish/ green circles, and if this is the case use a pink/beige corrector followed by concealer"). Your concealer should be creamy in texture and easy to blend, or it will crease.
To cover dark circles, "first apply light eye cream under the eye," says Brown. "It should be absorbed quickly and leave the skin smooth. Use a concealer brush or your index finger to apply in thin layers, and blend well. Bring the concealer all the way up to your lash line and into the inner corners of your eyes. Use more than you think you need and blend it into the skin, using your finger in a soft, patting motion. To lock the concealer in place, apply pale yellow powder over it and on the eyelids with a soft velour puff." And there you have it, concealers according to Bobbi Brown.