#3 - Mascara
Mascara is a subtle way to bring attention to your eyes and brighten your look. I recommend also using an eyelash curler, but since this is Top 3, I left it out of the list. I've been using Covergirl mascara, since it doesn't clump nearly as much as other mascaras I've used. I also recommend Ulta mascara.
#2 - Concealer
#1 - Exfoliating Lotion
(That wasn't intended to sound like a commercial, whoops! I swear I don't get paid for this, I just really love it!)