It's best to use a makeup sponge or a beauty blender when applying concealer. "You can use that to even out your concealer as well," says Jaliman. "Make sure the makeup sponge is clean and damp, then dab it over the concealer until it is blended. Using a damp sponge doesn't allow too much concealer to penetrate the sponge, and you will have more on your face and less penetrating in the sponge."
Most liquid concealers come with a brush wand, and it's fine to use that, but according to Jaliman, to get a smooth application, it should be blended with a sponge or beauty blender.