For a normal black man with normal black hair, how often should they wash their hair?

once a week....For a normal black man with normal black hair, how often should they wash their hair?
well i tell my brother to wash his hair everyday with conditioner and shampoo weekly his hair is nice a really soft. He now washes with conditioner 3 times a week and shampoos weekly like meFor a normal black man with normal black hair, how often should they wash their hair?
Twice a week, use oil, and dont forget to sleep in a doo rag so it doesnt get nappy