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If you have small eyes like Renee Zellweger:

What to use: Light, shimmery shades are perfect for opening up small eyes. Need we say more? Try a pastel eye pencil like MAC Eye Pencil in Pale Yellow, $13, which is a pretty color for summer.

How to use it: Line your eyes with a pale liner, dust a light eyeshadow (or even a bright concealer) over your lids and apply a shimmery highlighter right under your brow, Stern says.

What NOT to do: Scrimp on your lashes. You know what a padded bra does for your boobs? Well, lash primer does the same thing for your lashes. Thomas recommends using a lash primer first for an extra boost, and then adding two coats of mascara.