8 Big beauty sins

7. Using Makeup Testers

Why it's a no-no: Your chances of contracting herpes or pinkeye from the bacteria and germs found in the testers at a makeup counter are slim, but theoretically it could happen, according to Dr. Wexler. And let's face it, it's a little (okay, a lot) icky to share lipstick or eye shadow with tons of total strangers. Rehab: Make sure the store where you're shopping practices safe makeup sampling. Look for disposable applicators, sponges, cotton swabs, tissues, mascara wands, and rubbing alcohol for disinfecting makeup brushes, says Lyn Lynch, lead color specialist at Sephora. It's also crucial that you don't double-dip into the master container — ever. If you're not sure how to handle the testers, ask for help. Any reputable store should have well-trained sales associates. Also, wash your hands postshopping.

8. Popping Your Pimples

Why it's a no-no: You should maintain a strict hands-off policy when it comes to your zits. Can't resist? How's this for motivation: Messing with a pimple can extend its staying power to seven to 10 days instead of the normal two to three, since the dirt from your fingers can force bacteria into your pores and cause an infection, says Dr. Wexler. Rehab: Practice patience and apply either a benzoyl peroxide or salicylic acid potion twice daily — in three to seven days, it should be clear. In the meantime, squirt a cotton swab with redness-reducing eyedrops, then place it on your pimple. Follow with a dab of concealer.

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