If the cause of the question was not baldness, but insufficient growth rate, then as an option - sign up for a gym. Boosting testosterone production from exercise will have a positive effect on hairiness.
Firstly, do not disdain to buy beauty vitamins and drink them in a course. There is a loading dose of B vitamins and other useful things. Also - scalp massage: you tilt your head down, use your fingers to work the entire scalp with your fingers. With pauses of 30 seconds after each minute of massage, in total you will suffer like this for 10 minutes. Plus, "fire" hair masks. They will speed up blood circulation. Honey with red pepper, burdock oil with it, egg / mustard and the like will do. Hold for 15-20 minutes and make sure that the skin does not burn. Do not more than twice a week. The last thing is to use a hairdryer to a minimum, try not to wash it daily, so as not to dry the skin and wash only with cool water.