How do I apply this serum — on wet or dry hair, how much should I use, and where on the hair?

This serum is designed as a leave-in product for the lengths and ends of the hair. After washing, towel-dry hair until damp, then dispense a pea-sized amount (roughly the size of a 5-cent coin) into your palm, rub hands together, and distribute evenly through the mid-lengths and ends. For longer or thicker hair, you may need a second pea-sized portion; start with less and add only if the hair still feels rough after drying.

On dry hair, use a very small drop — barely the size of a match head — warmed between fingertips and smoothed over the ends to tame flyaways or add a polished look. The source notes the serum format spreads in a thin layer to seal the surface and limit friction, so a little goes a long way. Applying to the roots is not recommended unless your specific hair type handles richer textures without looking greasy.

Because it is lighter than traditional hair oils, there is less risk of weighing the hair down, but the exact amount depends on your hair density and condition. If the hair feels coated or heavy after drying, reduce the quantity next time.