Puppies in general have a very strong need to chew, some more than others. However, it needs to be controlled. But be sure you are providing a proper outlet for chewing, such as gumabones, etc. as you work on controlling the problem chewing.

Some ideas for discouraging finger chewing: when your puppy clamps down, let out a very loud YELP in imitation of a hurt puppy. Then, fold your arms and ignore him for 10 minutes.

With very young puppies, this sometimes works wonders - it's the same thing that happens when they get too rough with another puppy. The wounded puppy yelps and runs off, refusing to play for a bit. The yelp must be startling enough to stop the behavior. If nothing changes, you probably weren't a good enough actor.

However, depending on your pup's personality, this could also incite him to become aggressive and chew all the more (thought bubble: "I've wounded her, I'm going in for the kill!") In that case, you may need to use some aversive methods.

A first approach is to try Bitter Apple. Use it liberally, and not just a light spray. If you make a big impression the first time, it's likely to have a better effect. (If you doubt that, give it the lick test yourself!!!)

Some puppies need more. It's helpful if you could enroll in a puppy class designed especially for young puppies in order to get the proper guidance, because it's sometimes difficult for a novice trainer to recognize when aversives should be escalated. If you are reading the puppy wrong, increasing aversives could actually make the problem worse instead of better.

To introduce an element of "natural discipline", grasp the recalcitrant pup by the scruff of the neck with one hand, place your other hand over the top of his muzzle, gently pressing his muzzle towards his chest as you say, in a low, growly tone of voice, "No BITE".

If they begin to throw a tantrum and thrash around trying to bite, just hold the line until they "give in" and "say uncle" (quit resisting). You should not find it necessary to get aggressive with a young puppy. Simple restraint is usually enough to get the message across.

Absolutely do not use any stiffer discipline without guidance from an instructor. An example of overkill is the alpha roll. Most young puppies simply do not need that level of discipline, and you can really damage the relationship by using it.