The best foundation for hair growth is a clean scalp, says Yates. “Would you ever go days and days without washing your face? You wouldn’t, because the results would be horrific,” she says. “But that is what you do when you fail to wash your hair.” Not all hair types can handle being washed daily, making scalp rinses extra important for those who wear protective styles. Just don’t be too reliant on dry shampoo, as it can clog the follicle and lead to hair loss over time.

Remember that any product you apply to your scalp will penetrate more effectively if there’s no grime in the way. Ideally, you’d wash your hair a minimum of two to three times a week, says Yates, spending extra time massaging your scalp when shampooing. This helps promote blood flow (great for promoting hair growth!) and ensures all product, excess sebum, and dead skin cells are removed. Don’t feel the need to use a scalp scrub, as these can often be too harsh and damage the follicle—that extra massage when cleansing is enough.

While you should always follow the product’s instructions for use, most hair growth formulas will recommend daily or even twice daily application for at least eight to 12 weeks to see results, says Dr. Azizzadeh. You’ll want to apply it once your hair is clean and dry, possibly after dermarolling your scalp. “This can be helpful for penetration,” says Dr. Mian. Make sure you’re applying the peptide serum not to your hair, but to the root at the scalp, massaging it in. Increasing circulation as you massage will not only improve distribution, but increase absorption. “Several studies have shown simple daily scalp massage has helped to improve scalp health and helps to decrease hair fall,” adds Yates. Once you’re done, don’t wash your hair for at least several hours—and if you have nowhere to be, consider slapping on a plastic shower cap. “Covering the head in plastic adds warmth to further promote scalp circulation,” explains Dr. Kahn.