Be aware that scolding your puppy after it has misbehaved is fruitless. If you catch the puppy in the act of chewing, remove the object with a very firm "no." Let the puppy sense, through the firmness of your voice, that chewing is unacceptable. Correct your puppy quietly and firmly each time you catch him chewing. Realize that chewing is natural behavior for a puppy. It eases the discomfort of teething and is part of the puppy's exploring its environment through the sense of taste. Give your puppy safe chew toys such as rawhide bones and hard rubber toys. Avoid toys containing parts that might come loose and be swallowed such as plastic eyes or metal balls. Praise him when he plays with his chew toys. Never give the puppy a special sock or slipper to chew or a toy that looks like a slipper. Puppies cannot tell the difference between the toy and the real thing. Treat objects your puppy chews with hot pepper or with Bitter Apple for furniture, a bad tasting product available at pet stores. Boredom may also lead to chewing. Be certain your puppy enjoys play periods and enjoys walks with family members. Before leaving your puppy alone, take him for a walk or spend time playing with him. He will have less energy for chewing. Confine the puppy to his crate or to a small area, such as the kitchen. A pet gate may be useful in confining the puppy. Leave drinking water and chew toys.

http://pets.yahoo.com/pets/dogs/bt/puppy_chewing