This has been dealt with quite a bit and there are many answers.... Puppies learn a lot from their littermates in the last few weeks as to their biting and what hurts...bite inhibition... but that said i have a puppy that had no littermates and we are teaching her.... I use the "off" method... I always carry treats at present, my puppy is i think about 13 weeks old. So I have them on me ... When she goes to bite, I take a treat and I lure her off... as soon as she lets go I also say "off"... Now we only say "off" and she does not even bite. She was quite terrible, we called her the shark. When we say off now she sits in fron of us and looks. I do not like to pull, push or do anything physical to stop biting and I have found yelping can exite some, it did her, and they bite even more. Also ignoring sometimes does not work as she got more attention seeking.... the yelping and such works well in puppies that have had some good training in their litters from 8-10 weeks from littermates as that is the way they learn. Early puppies that have left their litter very early or singletons like mine, you start from scratch. I also like a mothyness on mine, so I allow biting or mouthing and if it is soft I stroke the puppy. I say off as soon as it turns into a firm bite.... i find the "off" and lured treat initially works really well for mine.... As I said Urshie is really good now, she hardly bites and if she has anything in her mouth, even objects, I say "off" and she lets go. it is also great training for the tugging games we have in the future and also the water training we do, though we change that to "thank you" when we ask for items, sound more polite.we reward good behaviour heavily. I do have time outs if she really is over the top, just a short period aways from all the other dogs and us, she hates that.... wetake her out , say nothing and when we let her back in we kinda ignore her too. She has got the hang of it all. I let my older dogs do what they have to do to keep her from being naughty withthem. they do help the training, especially my three older girls. The boys are a bit soft on her, but they do a great ignore.... Good luck training