START IN THE SHOWER
Go sulfate free. Overwashing can dry out your hair, so the less you shampoo, the more hydrated it will be and the longer it will grow without breaking. When you do shampoo, consider a sulfate-free formula; they often contain less harsh detergents, or none at all, and therefore help preserve your hair's natural oils. We like L'Oréal Paris EverPure Moisture Shampoo ($6.99). While lathering, remember that "shampoo is meant to remove product buildup and oil from the scalp, not the hair fiber," says Paradi Mirmirani, faculty member of the American Academy of Dermatology. Between washes, try Oribe Hair Care Dry Texturizing Spray ($39) to absorb oil at your roots and keep locks looking clean.
Stimulate your scalp. When you massage your scalp with shampoos containing peppermint or eucalyptus oil, you'll feel a tingling sensation. This helps increase circulation and blood flow to your follicles, boosting growth. Try John Frieda Root Awakening Strength Restoring Shampoo ($6.49) and Malin + Goetz Peppermint Hair Shampoo ($20). "Prior to washing, massage your scalp for 30 seconds," says New York and London trichologist Philip Kingsley. In one year, your hair can grow an extra inch, he says. Another option is a botanical leave-in treatment like Leonor Greyl Complexe Energisant ($54), which claims to stimulate hair growth when applied to clean roots two to three times per week.
Condition, condition, condition. When your hair is well hydrated, it is less likely to dry out and split, so use a conditioner even on the days when you skip shampoo. Your hair should be treated gently, like a delicate fabric, but it also needs to be regularly nourished, says hairstylist Oribe of the Oribe Salon in Miami Beach. Boston dermatologist Ranella Hirsch recommends applying a deep-conditioning product at least once a week. We suggest Kérastase Nutritive Masque Nutri-Thermique ($60).
STYLE WITH TLC
Brushers beware. If you're not careful, your hairbrush can actually do more harm than good. Ripping through wet tangles creates split ends, so try gently running a wide-tooth plastic comb like the version from Sephora ($4) from roots to ends. "When blow-drying with a round brush," says Kingsley, "don't pull too hard or you can break and pull out your hair." When you're not styling, avoid a brush altogether. "Brushing 100 strokes a day is completely old-fashioned and not a good idea," he adds.
Stop sizzling. Applying hot tools directly to your hair can fry the cuticle, so coat wet locks with a creamy moisturizing product for protection. We like Tresemmé Anti-Frizz Secret Smoothing Crème ($4.49). The best tools to prevent heat damage are ionic dryers and ceramic irons with uniformly heated plates (so you don't have to go over the same section more than once). Try the Sultra Laser Straight & Smooth one-inch iron ($145). For waves, hot rollers can be gentler than curling irons.
FAKE IT
Flatten out. To maximize your length quickly, eliminate volume at the roots, advises hairstylist Harry Josh. You want your hair to be as straight and flat as possible, "with a sleek Gwyneth Paltrow-type blow-dry." Use Blow Ready, Set, Blow Express Blow Dry Lotion ($21) before drying.
Choose products wisely. Smoothing out your frizz makes your hair look longer. Try Living Proof Straight Making No Frizz Styling Cream ($24) on wet hair. And, for a glossy effect, apply Avon Daily Shine Smooth & Shine Capsules ($8). The night before shampooing, try Michael Van Clarke 3 More Inches Pre-wash Treatment ($38) to help your hair retain moisture during and after your shower.
Clip it in. If you're into extensions, both Josh and Oribe recommend the clip-in kind. "Ken Paves's are the best. They're affordable and available across the country," says Josh. To keep them looking natural, "choose ones that really match your hair texture," suggests Oribe, and don't add more than three to four inches.
INSIDE THE SALON
Steer clear of scissors. Contrary to what some stylists say, haircuts don't stimulate growth. "If you're trying to grow your hair, do not cut the length, no matter how fried it is," says Josh. Instead, ask for your ends to be trimmed. For a style change, "short, blunt bangs will make your hair look longer, because the jump is so dramatic."
Restore with keratin. Go for a keratin treatment every eight weeks while growing out your hair, says Oribe. It smooths out the texture so there's less need for hot tools or dryers. Also, by coating hair with a protective layer, the treatments help protect colored or chemically straightened hair from further damage. For at-home keratin products, try Paul Mitchell's Awapuhi Wild Ginger line (from $16.95).
MONITOR YOUR HEALTH
Consider a supplement. For a boost, supplements like Viviscal ($49.99) "help reduce breakage and increase hydration, which is crucial to the growing process," says James Murphy, CEO of Lifes2good, which distributes Viviscal. The main ingredients are a blend of marine proteins derived from four types of fish rich in protein and amino acids. Josh has encouraged clients including celebs like Demi Moore, Cameron Diaz, and Hilary Swank to try these supplements for years. "You take one in the morning and evening, and in two months your hair growth will kick in at an accelerated rate," he claims. Some derms also suggest taking a multivitamin with biotin and a fish-oil pill to make your hair stronger. We like Functionalab 08 Hair, Skin & Nails
Check your meds. Did you know that some birth-control pills can cause hair thinning? Although it's typically not a direct cause and effect, "any changes in a woman's hormonal situation can yield hair loss," says Hirsch. Check with your doctor if you're concerned.
Manage your stress. "Stress causes the release of cortisol and other hormones that contribute to hair thinning," says Hirsch. The good news is you can reverse the problem by getting your stress under control. Scalp massage, anyone?