At first blush, a spray designed to make hair feel dirty doesn't sound like the perfect fix for flat, thin hair. It also doesn't sound, well, necessary. Can't you get dirty hair by doing... absolutely nothing for a couple days?

But IGK Down & Out Dirty Spray, $29, is a surprisingly effective volumizer, particularly for fine hair that's been damaged by coloring or heat-styling. Zeolite, a volcanic mineral, creates "dirty" texture and fullness while coconut and castor oils condition hair, making it easy to brush and restyle. Sprayed on the mid-length and ends of hair, it gives a sexy, piece-y look without making hair feel crunchy, stiff or dry. Chase Kusero, co-founder of IGK Hair Care, recommends that women with fine or thinning hair "lightly pulse" the micro-fine mist on the mid-lengths and ends of their hair, then use their hands to "rough up" the hair and create body. Another easy tip? "Spray on damp hair, twist or braid, and then air-dry to create volumized texture and wave," he suggests.

Buy now

For some women with limp or thin hair, volumizing powder is heaven-sent. But the look and feel of the product is a chalky, icky dealbreaker for others. Enter: KMS AddVolume Liquid Dust, $23. It's an ingenious powder volumizer delivered in a light serum, minimizing residue and mess. Best of all is its versatility: It can be applied when your hair is damp or dry, and to hair roots, ends or both.

Add fullness to freshly washed hair by "concentrating on the areas you want volume: at the roots, on the ends or in between," says KMS Global Style Council member Lori Panarello. "Then, blow dry hair using a round brush for ultimate volume."

If you're using the stuff on dry hair, "simply emulsify [the product] until it has a powder feel in your hands," Panarello suggests. "Then, use your hands to reshape hair by concentrating on the areas where you want additional fullness."

Buy now

A volume-boosting dry shampoo that's not a spray or powder? Now, that's some sorcery we had to see to believe. Indeed, Drybar Detox Whipped Dry Shampoo Foam, $24, infused with volcanic ash, plant proteins and vitamin B5, does the impossible: It soaks up oil in limp hair and adds body and bounce with barely any residue, a feat most spray-on dry shampoos can't accomplish.

The dry shampoo foam creates lift and soaks up oil at hair's roots in a matter of minutes, but that's not all. "It can also be tousled and scrunched throughout hair to create volume and bounce," says Drybar founder Alli Webb. "My girls with fine hair are telling me how much they are loving it."

Buy now

High-tech hair products with innovative ingredients are the domain of Living Proof, which is why we were so pumped to try Living Proof Full Dry Volume Blast, $29. This product's scientific achievement? Utterly weightless body and texture.

"I tell my clients to shake to activate, and I mean shake your head and the can at the same time," explains Living Proof Global Creative Director Michael Shaun Colby. That's because the product's patented volumizing and texturizing molecules (expandable textured aero-spheres, ETAS for short) are so light that they float in the can; shaking activates them.

"Hold your head upside down, shake the can, hold eight to 10 inches away from your head and spray the under-layers of your hair," he recommends. "Then, flip your hair back and spray through the top and sides." He promises this will give thin, fine hair "big volume, movement and texture."

Buy now

Most wave sprays give hair that fresh-from-the-morning-surf, piece-y texture. It's a sexy, (nearly) effortless look for women with fine hair. But salt can sap fragile hair of much-needed moisture and leave a crunchy feel. New R+Co Sail Soft Wave Spray, $29, lends body, definition and movement to hair, with a -- surprise! -- softness we previously thought impossible for wave sprays to deliver.

Whether you've got two minutes or 20 to style your hair, this volumizer can give shape to fine or thinning strands, says Robert Vasquez, lead educator at R+Co. "Once shampooed, I would spray Sail evenly throughout the hair, starting at the nap of the neck working my way up to the crown," he suggests. "You can either [blow-dry with a diffuser] for a more natural look, or dry the hair to create extra volume then use a curling iron or wand for a more polished look."

Buy now