Over the years, hair trends come and go, but one thing remains consistent: Hair volume is always a key component of the best styles. Glamorous curls embodied 1930's beauty; '70s waves were full of bounce and body; the '90s saw the era of voluminous layered cuts, and so on. Take a look back through history, and you won't find yourself feeling nostalgic for fine, limp hair—that's for sure. And, of course, full, volume-packed strands are still in today.

With that said, not everyone comes by this forever-fashionable amount of volume naturally. In fact, a lot of us have (unfortunately) flat hair that really could stand for a boost. For that reason, we're far from surprised that how to get fuller hair is one of the biggest haircare questions our Kiehl's Customer Representatives are tasked with answering. Here, we'll let you in on a little secret: It's all about using the right hair volume products. To pump up the volume of your mane, read on for an introduction to seven volumizing Kiehl's favorites.

1. Magic Elixir Scalp and Hair Oil Treatment

Good hair starts at the scalp. Before you reach for shampoo and conditioner—which surely are already part of your haircare routine—use a pre-shampoo scalp treatment. Try Magic Elixir Scalp and Hair Oil Treatment, a lightweight option formulated with avocado, rosemary leaf, and safflower oils. It promotes a healthy scalp environment, leaving both your scalp and hair feeling fresher. The oil also improves manageability, softens hair, and adds shine. Plus, it's suitable for all scalp and hair types, including super thin hair. Apply a small amount directly to your dry scalp and hair prior to shampooing. Give yourself a quick massage to work the oil in, then wait 10 minutes. Once time is up, you can rinse your strands and move on with your shower routine.

2. Amino Acid Shampoo

Shampoo is inarguably one of, if not the, most important haircare steps. Not only does it remove dirt and oil to clean hair, but the best formulas also prep your strands for the rest of your routine and can even impart other benefits like moisture, shine, and—our favorite—hair volume. Amino Acid Shampoo is a prime example. It cleanses and softens your hair while helping to add volume. This gentle shampoo with amino acids and coconut oil is a match for all hair types, and using it is no different than what you're used to. Wet your hair, massage it through your tresses, then rinse.

3. Amino Acid Conditioner

Picking the wrong conditioner can put you on a fast track toward flat hair. The issue is, certain formulas are capable of weighing down your locks and derailing your hopes and dreams of having voluminous tresses. We recommend coordinating your conditioner with your shampoo. Pair Amino Acid Shampoo with Amino Acid Conditioner—it's that simple. The conditioner is also formulated with amino acids and coconut oil (plus jojoba oil), and it has a light, creamy texture. Use it to help maintain your hair's natural moisture balance, strengthen hair, and make your mane more manageable. The result is hair that's shiny and healthy-looking. To see for yourself, apply the conditioner after shampooing, and let it sit for two minutes. When you're done waiting, just rinse.

Kiehl's Tip: There are small steps you can take to make your beauty routine more sustainable. One we feel strongly about is using refillable products when possible. You can purchase refills of Amino Acid Shampoo and Conditioner to help minimize waste.

4. Rice and Wheat Volumizing Shampoo

Rice and Wheat Volumizing Shampoo is also among the best hair volume products from Kiehl's. The shampoo, which is made with hydrolyzed wheat and rice proteins, as well as honey, is particularly great for fine, flat, and oily hair types. It gently cleanses and removes weighty residue without stripping your hair of its natural lipids. The formula also coats the hair with a volumizing complex for a thicker, healthier appearance. It helps build hair volume by adding body and reviving thin, lifeless locks. All you have to do is lather as per usual, then rinse.

5. Rice and Wheat Volumizing Conditioning Rinse

Again, it's a good idea to use a shampoo and conditioner that are formulated to go together. The above shampoo and Rice and Wheat Volumizing Conditioning Rinse make the perfect volume-boosting duo. Used in conjunction, the two hair volume products will help add body for fuller, thicker-looking hair. The conditioner also smoothes split ends and flyaways, helps detangle your hair, and leaves it with healthy-looking shine and silky softness. Just like the coordinating shampoo, it's made with hydrolyzed wheat and rice proteins and has a volumizing complex to help leave your hair looking healthier. When you apply the conditioning rinse, massage it on, wait two minutes, then wash it out.

6. Silk Groom Serum

When it comes to how to get fuller hair, the products you use in the shower go a long way. But what happens post-shower makes a major difference, too. What this means is, while haircare products play their part, styling products are equally key. Case in point: Silk Groom Serum. Plenty of serums can smooth stray strands and add a glossy sheen to your hair, but the wrong one could also give your mane a limp look. We love this serum with vitamin E and sunflower oil because it has an ultra-light formula that helps control your hair without weighing it down. It tames frizz and dry ends, protects hair from humidity, and boosts shine for a soft, smooth, and clean finish. Apply a few drops, and you're good to go.

Kiehl's Tip: Silk Groom Serum can be used on wet or dry hair, but the former offers an extra volumizing opportunity. Smooth the serum through damp hair, then use a blow-dryer to create additional volume. Place a round brush underneath your hair at the roots and direct the blow-dryer at them to add more lift.

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