Undereye circlesOver time, skin under the eye becomes thinner, causing the tiny veins within it to appear darker. Plus, the shape of the lower lid changes slightly, casting purplish shadows over the already dark undereye area. Allergies, sun damage, dehydration, and sleep deprivation, of course, can all make circles more apparent.
Fast fixThe best disguise is a creamy, yellow-based concealer, says Tabasum Mir, M.D., a plastic surgeon in New York City. Dot it on the inside corner of the eye and just below the lower lashes, gently blending it in with your ring finger (Prescriptives Camouflage Cream, $17, has an especially nice range of shades and textures).
To preventAre your dark circles chronic? Try an eye cream with vitamin K (to lighten the appearance of undereye veins) and retinol (to exfoliate), says Leslie Baumann, M.D., director of cosmetic dermatology at the University of Miami. It's pricey, but Dr. Baumann's pick contains both: Quintessence Under-Eye Serum, $71 for 60 capsules; 888-876-1138.
Large poresAlthough you can't change the actual size of your pores, you can make them look smaller by getting rid of dead skin and oil trapped inside -- just exfoliate!
Fast fixUse a mask with skin-sloughing alpha hydroxy acids (AHAs) or beta hydroxy acids (BHAs) once a week. Try Neutrogena Pore Refining Mask, $6, which has AHAs and BHAs and works in five minutes. After rinsing, use a moisturizer or foundation with pore-purging salicylic acid.
To preventExfoliate with a mask or scrub (save the washcloth for your body -- it's too harsh for your face) as often as possible, from once a week to daily, depending on your sensitivity.
Dull complexionFace it: After about age 20, your skin looks less vibrant because of slower cell turnover and decreased oil production.
Fast fixGet glowing with an easy exfoliator, such as Olay Daily Facials Lathering Cleansing Cloths, $7. Then use a moisturizer with subtly brightening ingredients like soy extract, mica, and vitamin C (we like Aveeno Positively Radiant Daily Moisturizer with SPF 15, $14).
To preventSwitch to a mild facial cleanser with an AHA like glycolic acid, a BHA like salicylic acid, or a combination of both, which will gently exfoliate dulling dead cells. Pond's Dramatic Results Active Hydrating Cleanser, $8, sloughs and revitalizes skin with AHAs, retinol, and vitamin C.
PimplesA freak zit is, in fact, not so freakish: Fifty-nine percent of women ages 25 to 40 get acne at least occasionally. The reason? Dead skin cells plug your pores, creating the perfect environment for bacteria, redness, and inflammation.
Fast fixDiminish redness and swelling with a tiny dab of hydrocortisone cream or a cold compress. Dermatologists advise against picking a pimple, but if you're going to do it anyway, do it right: Wait till it's almost a whitehead; apply a clean, wet compress (a very warm one to bring it to a head); make a small nick in the corner; and work it out by gently patting (but not squeezing) with a clean washcloth. Apply acne medication with 5 percent (or less) benzoyl peroxide, such as Clinique Acne Solutions Emergency Lotion, $13, to help kill bacteria and dry out the blemish. Then cover it up with concealer and translucent pressed powder.
To preventUse skincare products that are labeled "non-comedogenic" -- and no matter how tired you are, always remove makeup before bed. Try to keep your hands off your face. And if you're sick of breaking out right before your period, prescription antibiotics can help ward off hormonal breakouts.
Midday shineEveryone's skin produces oil. If yours does frequently, you're prone to having a shiny T-zone -- and, often, a makeup meltdown.
Fast fixUse oil blotters (like Clean & Clear Oil Absorbing Sheets, $5) to remove excess oil without smudging your makeup. In a pinch, separate a piece of toilet paper into two plies, then use one to gently pat the oil off your face.
To preventDon't wash your face more than twice daily -- overwashing stimulates the skin to make more oil.
Puffy eyesPuffiness can be caused by eating too many salty foods, drinking alcohol, crying, allergies, sun damage, even using too much moisturizer.
Fast fixApply a cold compress (or a bag of frozen peas) for five minutes to immediately reduce swelling. Follow with an eye gel that contains calming antioxidants, such as vitamin C, yeast extract, green tea, and caffeine (we like the cooling sensation of Origins No Puffery Cooling Mask, $20). Draw attention from puffiness by visually opening eyes with a pale shadow on lids, curled lashes, and black mascara on upper lashes only.
To preventProp your head on an extra pillow at night. Go easy on eye cream, applying it underneath the eye only (the upper lid is more sensitive and prone to swelling). Trade the late-night pretzels or occasional nightcap for herbal tea and fruit.
Dry patchesScaly areas crop up when your skin's natural oil production (which keeps moisture from escaping) is disrupted, whether it's from cold weather, dry air, scrubbing yourself too roughly, or using products that are harsh on your skin.
Fast fixLightly buff away flakes with a gently exfoliating cleanser (we like nondrying Bioré Mild Daily Cleansing Scrub, $6). Or try a recipe from the Flying Beauticians Salon, in San Francisco: Mix an egg yolk with a tablespoon of honey; apply to face for ten minutes; and rinse -- it will soothe and hydrate skin. "If the area is extra irritated, apply hydrocortisone cream, immediately followed by moisturizer," says Dr. Mir. Pressed powder makes dry skin more obvious, so opt for a liquid foundation or just use concealer.