Nipping is really all about testing - testing your will for dominance and testing their new teeth. The very best way to put a stop to biting and mouthing of fingers and hands is to speak in dog language! The next time your dog nips you, make a high-pitched yelp like a dog that has had a toe stepped on. Your pup will be very concerned! Take that time to "change the subject" by throwing a toy or launching into a training session.
Scolding your puppy for finger nipping really doesn't work. When dogs play with each other, there is plenty of growling and threats - bluffs mostly. Your dog will think that you are just raising the stakes and that makes him want to keep playing the nipping game.
Some trainers advocate grabbing the dog's tongue or lower jaw as punishment for nipping. This too is ineffective because the dog will just try to outdo you in the nipping game.
Finding kindly adult dogs for your puppy to play with helps with nipping quite a bit - older dogs simply will not tolerate being nipped with a puppy sharp new teeth and will put the puppy in it's place. This is a very important step for your pup since often they simply don't know how painful their bite is until they are "told" by another dog!
Another important point to keep in mind with nipping is prevention. You will find that there are certain times when the puppy does most of it's nipping - when playing with toys, when it has not been exercised in a while or when it's glad to be reunited with you, most likely. At these times, simply keep your fingers away from the dog's mouth! Take the dog outside to burn off some energy and/or simply don't pet and stroke your dog when it is already over-stimulated. Often, nipping is a way for the puppy to tell you that it's anxious about something - that you will take it's toys away or that you will leave it alone again, most likely. Follow the above tips, help your puppy to burn off excess energy with a brisk short walk and use common sense - you will see improvement with nipping fast.
