Biracial hair care.

Amanda
My son is mixed. African American, Caucasian, and Mexican im not sure how to do his hair or if i should cut it since he still has some bald patches. His hair is curly and i do not have a clue on how to take care of it since its diffrent from my own.. i hear alot of diffrent things on washing, brushing and styling. Any tips, and suggestions please.