So, full brows are really big. Forget the pencil thin eyebrows they are not doing you any favors, but if you are filling in your brows do not use eye shadow. Eye shadows commonly contain more than actual brow powders, so itâ€™s more likely to smudge and smear. You run your fingers through your hair and get a little close to those eyebrows and you are going to be looking foolish. Letâ€™s avoid that and just use powders designed for your brows.