There is a fine art to applying to eyeliner under the eye. If the line becomes too thick your look can go from classy to nasty really quick. Mila Kunis popped up with the best under eye liner job I’ve seen in recent months. To copy Mila’s look you’ll need a flat tip eyeliner makeup brush and a gel eyeliner. A super-sharpened eye pencil can do the trick, but it also can go on too thick really easily.