Beauty Treatments: When to DIY and When to Go Pro

Glycolic Peel: DIY

These peels contain glycolic acid, an anti-aging ingredient known for its ability to improve skin texture. Glycolic acid weakens the glue-like substance that holds dead skin cells together, encouraging exfoliation. An over-the-counter glycolic peel can make your skin glow by buffing the surface and, over time, diminishing pigmentation and fine lines. You should start to see results after a month of consistent weekly use, says Doris Day, MD, author of Forget the Facelift and a New York City dermatologist. (If you want faster results or major skin resurfacing, consult your dermatologist, says Day.) While an at-home peel is less potent than a professional treatment, it can still be irritating. Neutralize or remove a peel immediately if you experience discomfort. Skip glycolic peels if you have sensitive skin, eczema, rosacea, sunburn, an active infection, or use Retin-A.

Waxing: DIY

You can absolutely get the same results waxing at home as you would at a salon, says Cindy Barshop, founder and owner of Completely Bare Hi-Tech Spa. The catch: You must be able to see the area you’re waxing to apply and remove the wax with your dominant hand. Always follow the directions on the kit (Barshop is a fan of cold wax, which does not require heating.) See a waxing specialist if you have sensitive skin, extremely coarse hair (which is more prone to in-growns and, thus, better suited for an expert), or you're removing hair you cannot see, says Barshop. In other words, leave Brazilians to the pros.

Brow shaping: Pro

Everyone should see a pro at least once to get an understanding of what her ideal shape is and instructions on how to maintain it herself, says Joette Balsamo, celebrity makeup artist and brow specialist at the Marie Robinson salon in New York City. Ideally, you should check in with an expert a couple times a year to make sure brows are on the right track. The key to tweezing between appointments? Don't over-pluck, says Balsamo. Start by ditching the magnifying mirror, which makes it too easy to lose perspective. Then, create a boundary by filling in brows with a pencil or powder to form their ideal shape. Clean up hairs that fall outside the shaded area, but never tweeze along the top edges or beneath the inner corners. Taking too much off the top can cause brows to appear lower, adding years to your look, while removing fine hairs under the inside corner may leave a bald patch.

Gel Manicure: DIY

These manicures stay shiny and chip-free for up to two weeks, thanks to a polish that combines acrylic with solvents found in traditional polish and requires a UV or LED light to set each coat. The benefit? There's no dry or wait time at the end, says celebrity manicurist Kimmie Kyees. When you walk out, you can't mess them up. Do-it-yourself alternatives can mimic salon manicures, says Kyees, but patience is key. The 10 to 15 minutes you save in drying time should be spent on application. Use ultra-thin coats to ensure a smooth finish and keep polish off skin and cuticles. Wipe away excess polish before putting nails under the lamp (many at-home kits come with a mini light), or else the polish will harden and stick. If you're all thumbs when painting, try the at-home gel strips. And always do one hand at a time, says Kyees. Caveat: Skip gel manicures altogether if you pick at your polish -- doing so will wreck your nails.

Hair Color: Pro

The challenge with at-home color is achieving an even application when you can't see the back and sides of your head clearly, says Eva Scrivo, owner of Eva Scrivo salons and author of <em>Eva Scrivo on Beauty. Not only can a professional ensure precise application, she can also create a color that flatters your skin tone (the wrong hue can age you and make skin look drab) and apply different formulations to various areas, such as gray sections or dry ends. A stylist can also combine highlights, lowlights, and a glaze to add numerous subtle tones to your hair, making it look more natural, says Scrivo. To buy time between salon visits, stick to at-home touch-up kits that apply color to clearly visible areas -- along the hairline and part.

Teeth whitening: DIY

Every decade, teeth darken one or two shades, says Dr. Emanuel Layliev, DDS, at the New York Center for Cosmetic Dentistry. To turn back the clock, try over-the-counter whiteners, which contain peroxide that forms bubbles on tooth enamel and lift away stains. At-home strips can get teeth almost as white as a pro treatment, says Layliev. They just take longer. If you have gum recession or worn down tooth edges (or want instant results), consult your dentist for in-office whitening. Professional sessions tend to cause less sensitivity than at-home whiteners, says Layliev. Dentist-dispensed trays, which are custom made for a closer fit than store-bought trays, can also decrease irritation. Teeth with yellow or brown undertones are most likely to whiten. Skip bleaching treatments if your teeth look gray next to a piece of white paper, as this discoloration won't respond to peroxide.

Lash Extensions: DIY

Professional lash extensions -- in which a single lash is bonded to each of your own top lashes -- can easily set you back a couple hundred dollars and require touch-ups every few weeks. Drugstore lashes, however, can create a dramatic effect for a fraction of the cost. For the most natural look, choose individual lashes labeled short and knot-free, says Balsamo. First, apply eye makeup including mascara. Then dip the end of an individual lash (which are actually small clusters) into a pea size amount of glue and apply it to the middle of the eye, above the pupil. This creates a youthful, open look. Stop there, or, for a fuller look, dip your next lash into the bead of glue and work towards the outer corners. Avoid placing lashes only at the outer corners, says Balsamo, as it can make eyes appear droopy. For the fullest look, place a few lashes toward the inner corners.

Blow Out: Pro

When you need a blowout with staying power (that can last through a few days of events) or you want a look you're not comfortable tackling yourself (waves on straight hair or straightened-out curls), a salon appointment is the only way to go. The main advantage to a pro blowout is the longevity, says MariLynne Mele, stylist at Blow, the New York Blow Dry Bar. It also makes hair shiny, bouncy, and polished, and instantly makes a woman feel pulled together. To prolong a salon blow dry, use a shower cap since humidity can cause frizz. Sleep with your locks pulled into a very loose bun at the top of your head, secured with a hairpin (a hair band can leave dents). Use a dry shampoo to absorb oils near roots and scalp so hair feels clean and refreshed. Can't make it to the salon this month? It's possible to get similar results at home, says Mele. The secret? Apply an alcohol-free styling lotion to damp hair to help tame frizz; dry hair completely (if it feels cool to the touch, it's still damp and more likely to frizz); and use the right brush.The bigger the brush, the straighter the hair, says Mele.

Sunless Tanning: Pro

Because streaks are the saboteurs of self-tans, a visit to a pro is essential to obtain absolute even color, says Barshop. A salon spray tan will last longer than one applied at home, and a professional can add definition to your abs or arms by darkening certain areas, if desired. Schedule the service a minimum of 24 hours before a special event and shower at least once afterward to prevent the tan from rubbing off on clothes. If your want to boost color on your legs and arms for warm-weather outfits, you can get good results with an at-home self-tanner, says Barshop. Try the gradual lotions that slowly build color over a few applications since they're less likely to streak.