DO ignore your puppy and/or go limp when he begins biting you. You can also give a sharp “Yip!” or “Ouch” which will startle your puppy and stop the biting. Then praise him calmly when he stops.
DO offer your puppy a toy to bite instead of you, and praise him when he switches to the toy.
DO stop all interactions and walk away if your puppy continues to bite.
DO work to train your puppy to use his mouth gently. Wave your closed fist in front of his face and pull it away if he tries to nip. Try it again, and if he does not nip, give him a treat. Make sure the treat is in the opposite hand you are presenting. Try this with other objects, your open hand, your finger, and finally a toy and eventually give him the toy before he nips. Lengthen the time he has to wait patiently before giving him the treat and/or the toy to play with. You are teaching him he has to wait for permission in order to play/nip.