To use this concealer, first, clean your face and apply a moisturizer. Then, take a small amount of the concealer with a concealer brush or your finger. Gently dab it on the areas you want to cover, like post - op discoloration, scars, or under your eyes. Blend it well for a natural look. For the green concealer, focus on areas with deep redness. And for the yellow concealer, use it on areas you want to lighten. Remember to close the container tightly after use to keep the concealer fresh. Store it in a cool, dry place. If you have sensitive skin, it's a good idea to do a patch test first.