How to Test Every Kind of Makeup

Some of us are lucky enough to find foundation that always looks natural or mascara that never ever smears. Then there are the rest of us. But with these foolproof tips, you can make sure you love the products you buy—without using testers on your face. (Unless you see them being opened, consider them contaminated with bacteria, says dermatologist Heidi Waldorf.) Here's what to look for, whether you're shopping at the drugstore, a department store, or online.