Problem: Too thin, unflattering brows. "When you get a clear look at yourself or have been reprimanded by a friend or professional that your brows are too thin, step away from the mirror, put down the tweezers and start from scratch," says Stiles.

Solution: You need to let your eyebrows grow back in -- all of them. "This is one of the most difficult beauty dilemmas to address because it is so tempting to clean up all of the new hairs growing in," says Stiles. "But you have to let them all grow in to really see which brow shape will best compliment your face."

To quell the urge to pluck, try masking new growth by filling brows in with cake or liquid eyeliner (try Laura Mercier Eye Liner, $20), which allows you to control the density of pigment and even paint on faux hairs if you need to. "For best results, use a very fine, thin, long brush (like Shu Uemura Natural Brush 2R, $14)," says Stiles.

If you are blonde or brunette, use a light/dark brown color. If you have dark brown or black hair, use a black cake liner, keeping it very diluted and building as you go. Also, if you can't afford to see a brow professional regularly, just go a few times until you learn the best shape for your face and have mistakes corrected so you can better maintain them yourself.

Problem: Dark lip shades (such as colors in brown, black, purple or maroon -- think goth) can look aging.

Solution: Avoid lining lips with dark lip liner at all costs, especially if you're not planning to fill them in. If dark lips are a look you're deeply attached to, try a different version of it. Shift to a dark lip gloss if you must, or a sheer version of what you're used to. Try Clinique Almost Lipstick in Black Honey, $14,which is a sheer but deep berry color. Another option is to try a sheer lip pencil if you want your look to last, since glosses and sheer lipsticks tend to wear off more quickly. Reapplying more often is a minimal trade-off for a more youthful and modern look.