To improve the growth of beard hair you need to maintain a healthy circulation. And maintain your hair follicles and sebum; to improve them a healthy diet of vitamins is required. Vitamins A, C and E should be taken in a balanced way. This will help in the growth of facial hair.
Physical activity stimulates the growth of facial hair. Daily exercises can go a long way to increase the blood circulation that in turn increases the growth of facial hair. If you exercise daily for at least 20 minutes it will make a big difference and will help in the growth of facial hair.