A puppy who bites while playing is not doing anything wrong. He just doesn't know that biting hurts!
I find that the most effective way to deal with puppy pinches is to scream as if you've been burned. Most of the time this is disarming, as the puppy freezes stunned, and tries to figure out what happened. Sometimes you have to add a slap on the nose, but this is rare.
Some canine behaviorists believe that this can be avoided. More than once and more I have come across mentions of the "social punishment" or "freezing" technique in profile articles. Its essence is simple: as soon as the puppy grabs the hand, the person immediately turns away from the varmint and freezes. This lasts only a few seconds, during which time the "offended" person pays no attention to the puppy.
The method is based on the use of ignoring as punishment for a misdemeanor. In other words, we don't do, we don't do. Since communication with a partner during play plays a major role, a brief "social freeze," that is, deprivation of communication, becomes an unpleasant and undesirable consequence of a puppy bite.
With excitable puppies, as with those with a rich practice of hand chewing, patience will be needed. Time-outs will most likely have to be done over and over again. "But as long as biting and chewing is a social behavior, social punishment will work."