I'm by no means an expert, but here's what works for me: When Toby arrived (about 3 months old), he was extremely nippy when he played. The more excited he got, the harder the bite. Since Toby responds better to more positive redirection (rather than a loud, angry, NO!), I say "OW!" in a loud enough voice to get his attention, I look away and stop playing with him. He learned quickly. He's catching on that if he wants me to play with him, he has to be more gentle. Good luck!
There are two good ways to approach this. One is to say "ouch" in a very loud, high voice. Think of two puppies playing. If one gets to aggressive, what happens? One puppy yelps. Consider the "ouch" as a yelp. Play should stop. Step two, play stops and then the puppy is ignored for a short time. No attention until the puppy is quiet and submissive. Again, consider what your dog wants: food and attention. If attention is removed, your dog must figure out what will get your attention again. If being quiet gets your attention, then your dog is more likely to repeat that behavior. Consider canines in packs; if one of the sub-dominants is acting outside of the norm for the pack, the pack isolates that canine until it starts acting as it should. At that time, the canine who has been isolated is reintroduced to the pack. Dogs are social animals and don't like isolation. Therefore, by removing play you are effectively isolating the puppy and waiting until he/she is calm. Then return to play, but gently. If it escalates, repeat the correction.
Puppy biting is quite a normal activity. The problem lies when we as owners allow it to continue. The loud "ow" is effective for some. Sometimes a firm snout grab with a command "no bite" works well. Still others will use a small spray bottle of water to make a quick redirection. What you may look at here is just how you are interacting with him that elicits the bite. If you are playing hand games with him you need to come up with a better plan. Never use your hands when his mouth is still if full gear. Make sure all physical play is with an object of play. If you are playing tug o' war make sure the item you are using is of sufficient size so your hand is not a part of it. Lastly it us usual for a dog that reaches a high excitement level not to discern his reactions to some things. This should be a time to quickly end the game. Teaching a pup to start and end a game is a great tool that will help you far into adulthood. I have used the command "enough" with great success. When playing fetch also teach him to "drop it" so you do not tussle over who gets the object at the time. Dont forget this biting is very typical to the way pups interact with each other. This is something that you have to make him understand.
A big fat carrot works well, and so does a rope. I did find the cutest stuffed animals, but I can't remember the name...they lasted SO much longer than the other stuffed toys! Junebug's favorite chew is a "bully stick", which is a cured tendon. It's softer than a bone, but not flakey like rawhide. It takes her about 3 days to get through one!
Well my idea of biting is: Even a puppy shouldnt bite (at least not in you). Cause if you say "Ow" with a high voice, you are a puppy yourself! And what you want to be is a packleader. Ive never seen a puppy bite in a older dog like the puppy`s we raise bite in us! Its just a lack of respect (and there right to, cause we never tell them otherwise in a right manner). And ive never ever seen a puppy bite in a packleader like that! When I got my corgi, he wanted to bite me as well. But even the first day that I had him, I would correct him! because if he can do that when hes a puppy, he can also do that when hes older (and his teeth arent so cute anymore). A dog cant understand why he can do it when hes a pup, and he cant do it when hes older! dogs just dont think that way. Yes should always be yes, and no should always be no!
And a cow-hide (I dont know how to call it otherwise) bone is very good for the teeth, and gives them something else to bite (and not in you;-)
Well I train my dog with Natural Dogmanship, and you learn to see everything from a dogs kind of view. The best correction (cause its not a punishment) is to give them a "Neckbite" (I dont really know how else to call it in english). You warn the dog with a growl, just a grrrr (a serious one, not a funny one, theres a big difference for the dog;-) or you can use a NO with a low mad voice (if you cant growl). Then you just give him a little bang/nudge in the neck. Not to hard! after a while your dog gets to know this, and i can even correct my dog from a big distance, just with a grrr.. ;-) Its a natural way, you see mother dogs do this to there pups, and adults as well.
I do want to say again that this is a correction, not a punishment. We only punish the dog when he shows aggression in any kind of way. (biting(the reall thing), growling at you etc)