Before you even turn on the faucet, use the pads of your fingers to gently massage your scalp using a technique that mimics squeezing an orange. Elizabeth Cunnane Phillips, a trichologist at the Philip Kingsley Clinic in New York City, says, "Palpating the scalp increases blood flow and kick-starts the exfoliation of pores that harbor excess sebum." Use a volumizing shampoo and conditioner loaded with rice or wheat protein, which strengthens and expands the diameter of the hair shaft. And remember, your roots are naturally hydrated by scalp oils, so only condition ends. To rid your mane of dulling product buildup, use a clarifying shampoo up to twice a month.

To pump up the volume, eschew sticky hairspray and set your style with a starch-based dry shampoo, which is formulated to zap slippery sebum and lift hair right at the roots. Swear off styling products loaded with heavy waxes and silicones, which will only make lifeless locks look more languid.

Ultrafine or thinning hair could be an indication of dietary shortcomings like a lack of iron, B12, or zinc, says Cunnane Phillips. It could also be a sign of a more serious condition like a thyroid disorder, so it's important to check in with your doctor to help clue into the cause. If she gives you the A-OK, you may want to contemplate taking a nutritional supplement like Viviscal ($50). Fortified with an AminoMar C Marine Complex, horsetail extract, and vitamin C, Viviscal demonstrated a 46 percent reduction of hair loss after 10 weeks in clinical studies. Seventy-five percent of study participants also perceived an increase in overall volume and thickness.

When you don't have time to shower, soak up excess oil with a spray- or brush-on dry shampoo. Scan the label for corn, rice, or oat starches, which are powerful sebum-absorbers that won't leave behind a chalky residue like talc-based powders do. Need to oil-erase on the go? Dab your hairline and face-framing front layers with blotting papers, which are portable sheets formulated to sop up sweat. If you're really in a bind, you can always reach for a roll of oh-so-glamorous paper towels.

To camouflage a receding or thinning hairline, ask your stylist to snip soft side-swept bangs. This flattering fringe frames the face, creates the illusion of fullness, shortens a high forehead, and draws attention to your eyes. If you're concerned that bangs will be too much upkeep or that they'll constantly fall into your face, ask your hairdresser to cut front pieces long enough so that they can be tucked behind your ears.

Don't let wilted locks keep you from wearing your hair down; add tousled texture in minutes. Luca Blandi, a stylist at Oscar Blandi Salon in Manhattan, suggests spritzing dry hair with a saltwater beach spray (try Bumble & Bumble Surf Spray, $23) and creating two-inch-wide braids around your head, securing the ends with clips or elastics. Grab a flatiron and run it over each braid, then undo the plaits, flip your head upside down, and finger-comb from root to tip. Finish with a shot of invisible dry shampoo, which sponges up any excess grease so your style stays lively all day long.

One way to create the illusion of a thicker head of hair is to add dimension with highlights and lowlights. Lowlights act as shadows simulating depth, while shimmering highlights attract attention to the surface of the hair. The effect is similar to an optical illusion, making a thin mane look lush, whereas uniform color can make tresses look flat and drab. Another reason to consider color is that dye pigments temporarily volumize the hair shaft by absorbing oil and sealing the cuticle.

Postshower, comb through a volumizing mousse and allow hair to air dry no more than 20 percent, otherwise your mane becomes harder to manipulate, says Alli Webb, president of Drybar in Los Angeles. Using a boar-bristle brush, flip your head upside down; hold the brush in your dominant hand and the blow-dryer in your nondominant hand, and direct hot air toward roots for maximum movement. Once hair is 75 percent dry, straighten up and focus on front layers. Webb also suggests curling ends with your brush and blow-dryer or "setting your hair in Velcro rollers while it's still hot, and then letting them cool." Give your style some staying power with a spritz of dry shampoo.

To create big, bouncy waves in super-straight hair, grasp a clamp-free curling iron like the Amika 25mm Tourmaline Curler ($139) and hold it upright. Starting on the left side of your head, wind a one-inch section of hair around the iron's barrel, rotating counter-clockwise; hold for 10 seconds. When twisting tendrils on the right side of your head, wind strands clockwise. This ensures that coils are curling outward and away, framing your face instead of falling forward. Finish by misting your brush with a flexible-hold working spray, then gently combing waves so they start to stretch out.