Why: A typical 20-something can show up at the office with heavily rimmed eyes, and it looks edgy. But in your 30s, it just seems like you partied too hard on a "school night" and forgot to wash your face. Instead of playing up your baby blues with eyeliner, define your eyes by shaping your brows. Filling in your arches actually lifts your entire face (again, it's too early for a real face lift).
Try: There's a reason the Tom Ford Brow Sculptor ($44) is a cult product. Use the spoolie brush to comb hair up and over, then flip it, and with light, upward strokes, fill in any sparse spots with the calligraphy tip. Be careful to only add more definition to the top of your arches, since you want to create the illusion of a lifted brow. Fun fact: twist the cap of the Tom Ford tool counterclockwise to reveal a sharpener.