Never allow your puppy to bite. This sort of thing will become a bad habit and be hard to break later on. A puppy that is allowed to nip and bite becomes very bold and aggressive as he grows older. Many owners are so upset by theirs dogs' uncontrolled behavior and aggressiveness that they decide to give their dogs away. Unfortunately, what they do not realize is that the next person does not want a problem dog either and more than likely the dog will shortly end up at the pound for euthanasia.
Teach your dog to be gentle by offering tidbits/toys in your hand. If he snatches the tidbit, yell out "OUCH" and whimper and pout while withholding your hand and tidbit from the pup. Tell him you won't play with him anymore and turn away and ignore him. A few minutes later do the whole routine over again. Be very melodramatic with the verbalizing and acting. The pup wants the food/play and will gentle down eventually. Offer it to him again and when he hesitates or is gentle in taking the food/toy, let him have it and praise him for his gentleness. This can proceed to the extent that you can teach him to put his mouth over your hand but not press down. It takes patience but can be done.
Puppies and dogs that jump on you are only looking for attention. If when you enter a room and your puppy dashes over to greet you, crouch down to pet him. This also helps eliminate submissive urination. Otherwise, ignore the pup briefly till it calms down somewhat, then pay it attention by petting it only when all four feet are on the ground.
If the dog manages to jump up onto you, grab the front paws with each of your hands and squeeze firmly until the pup is in discomfort and struggling. Then say "OFF" and at the same time release the paws and toss them off to the side. When the dog is properly on the ground, pet it and praise it for standing well. You may even train it to sit for the pets. Just make it sit, then pet only while sitting. Consistency is the usual requirement here. EACH and EVERY time the dog jumps on ANYONE, they must go through the paw squeeze, "OFF" and toss, praise for all 4's being on the ground. It doesn't take long if the dog is made to be uncomfortable while jumping up. Avoid knees in the chest and stepping on toes (other folks methods). These can only cause damage to many a dog.
Work at petting the dog only when it is calm. Give it commands to help it along, like "be easy and stand" or "sit". Let the dog know that you are happy with it and it can be confident you still love it.
