Problem 1: Ghostly Pallor
Self-tanners can serve as a soft-focus light on your legs—blurring dimples, fading scars, making veins look less conspicuous. We tested dozens of them to come up with our favorites, and in the process we figured out the best way to apply them.

Exfoliate. Since self-tanners react with the upper layers of your skin, if certain areas have thicker skin than others, your "tan" will be more concentrated there. In other words, you'll be splotchy. Buffing your skin with a scrub evens the tanning field. Give scalier areas, like your knees and feet, extra attention.

Moisturize. A thin coating of moisturizer smoothes the surface of your legs and prevents streaks. It dilutes the self-tanner a bit—but what you lose in intensity you make up for in uniformity.

Apply. The directions on the bottle might tell you to start from your feet and work up—but don't. "Think about where the sun hits," says Kara Peterson, who trains aestheticians in the art of fake tanning at Clarins spas. "Start off in the middle of your thighs and the middle of your calves and blend out." Your feet and knees should get only whatever's left over. Also, do the job standing up, says Peterson—when your knees are bent, you might apply too much to the stretched skin.

Shimmer. After your self-tanner has done its work, blend a slightly iridescent lotion over the front and back of your thighs, along your shins, and down to your feet. "The strategically placed shine has a slimming effect," says Linda Hay, head makeup artist for Victoria's Secret Beauty. If you have olive or dark skin, you're lucky—just do step four.

Problem 2: Scary Bruises
Do your legs often look as if you just played a game of one-on-one with David Beckham? You probably haven't gotten clumsier—but you may have lost some padding. "As we age, we lose the fat just beneath our skin that protects our blood vessels from trauma," says Francesca Fusco, MD, assistant clinical professor of dermatology at Mount Sinai School of Medicine.

You can't do anything about the fat loss, but you can cut down on medications and supplements that make you more prone to bruising, such as aspirin, ibuprofen, and vitamin E. Fusco also recommends taking 250 to 500 milligrams of vitamin C, which can strengthen collagen in the blood vessel walls, every day.

Once the damage is done, bromelain supplements may help the discolored areas heal more quickly; take 500 milligrams twice a day, says Leslie Baumann, MD, professor of dermatology at the University of Miami School of Medicine. Anecdotal evidence also suggests that topical arnica creams (try Boiron Arnicare Cream, $6) speed healing.

Problem 3: Saggy Knees
We think it's a fine idea that our knees are located smack in the middle of our legs. Without knees, so many delightful things—walking, line dancing, the lotus position—would be a challenge. But when we recently noticed that our knees weren't looking as taut as they once did, their prominent placement began to seem unfortunate. Firming the quadriceps may improve things.

"Tightening the muscles above the knees helps lift them," says Johanna Subotovsky, a trainer at Equinox Fitness. To boost quadriceps strength, sit at the edge of a chair and extend each leg until it's parallel to the floor.

The only way to fully restore knees to their former glory involves surgery: No thanks. A less-invasive option could be coming soon. Doctors are investigating laser and radiofrequency treatments (brands include Titan and Thermage) as potential knee-lifters. These procedures heat collagen, causing it to contract and tighten skin over time; one treatment (about $3,000 for both knees) is supposed to yield results over six months, and the effects can last up to two years. "I'm not confident in these treatments yet, but as the technology evolves, the knees will be an area that could be treated successfully," says Ranella Hirsch, MD, president of the American Society of Cosmetic Dermatology & Aesthetic Surgery.

Problem 4: Visible Veins
Maybe you noticed a couple of faint squiggles around your ankles a few years back. Now you see blue lines, like kudzu gone wild, creeping behind your knees, over your thighs. You have several options to get rid of them, depending on the type of veins you're dealing with; all require a doctor's appointment.

Itsy-Bitsy Spiders: The tiniest veins can be zapped with a Vbeam, YAG, or diode laser. The beam destroys the walls of the veins (it will feel like a few quick rubber-band snaps), causing them to disappear within about two weeks. About three treatments, at $300 to $400 each, are necessary.

Smooth Squiggles: When a vein is large enough to be threaded with a small needle, sclerotherapy is the most effective option. A solution is injected into individual veins to irritate and collapse them; the body then reabsorbs them over the following weeks. Glycerin works for smaller veins, and saline or Sotradecol (a sodium sulfate compound) is most effective on larger ones, says Neil Sadick, MD, clinical professor of dermatology at New York–Presbyterian Hospital/Weill Cornell Medical Center. Two or three treatments are usually necessary, and the veins look worse before they get better (in about a month). Treatments cost $300 to $500.

Ropy Bulges: When veins protrude, doctors recommend "endovenous closure," a procedure performed under local anesthesia in which a radiofrequency or laser fiber is inserted into the vein; energy is applied to heat the vein's walls, causing it to collapse. One treatment is sufficient, but can cost from $3,500 to $6,000 per leg (doctors usually treat one leg at a time).

Problem 5: Lumps & Bumps
Cellulite is a fact of life for about 90 percent of us, and as of yet, there's not a lot we can do about it. A few high-tech machines are approved by the FDA for a temporary reduction in the appearance of cellulite (there is no indication how long results might last).

VelaShape and SmoothShapes are the most promising at the moment. VelaShape combines radiofrequency and infrared light energy, suction, and mechanical massage, and SmoothShapes is a hybrid of laser, light, massage, and suction. Most doctors say a series of treatments will noticeably smooth bumps—but consistent maintenance is necessary. VelaShape requires a touch-up every three to six months; SmoothShapes requires one at least once a year.

Liposuction is a one-shot deal, but even this invasive procedure won't necessarily improve cellulite. "Sometimes it helps, sometimes it doesn't, and sometimes it makes cellulite worse," says Heidi Waldorf, MD, director of laser and cosmetic dermatology at Mount Sinai Medical Center. You can suck out some of the fat, but you can't do anything about the fibrous bands that create dimpling. (This is also why all the squats, lunges, and leg lifts in the world won't help cellulite.)

Mesotherapy is a catchall term for injecting who-knows-what into cellulite in an effort to liquidate it. "It's not regulated," Francesca Fusco says. Lipodissolve involves injecting a specific ingredient that has been shown to dissolve fat (in test tubes). "There have been reports of some very scary side effects, though," Fusco says. "It's promising, and some very respected doctors are conducting studies, but I wouldn't recommend it anytime soon."

Topical cellulite creams contain ingredients (usually caffeine or a derivative) that act as diuretics, removing moisture from the skin, which makes it firmer for a few hours. (So: Rub it in, get to the beach, and get back fast?) Some of these creams also contain retinol, which helps refine the surface of the skin and can boost collagen production. Over time, retinol improves the texture of your skin (but not your cellulite).