This is what Isadora has done to my clothing. She, being an Australian Shepherd from a herding line, is all teeth. She mistakes me for cattle or sheep all of the time. I guess her parents didn't teach her the difference between cattle, sheep and the hand that feeds you.
Obviously, I have only two shirts and two pairs of jeans that I wear whenever I have Izzy out of her playpen. She actually HAS gotten better in the weeks that we have had her. Though, everything that I read did not work: 1) Make a loud "yipe"-like sound like her littermates might have done to say "Ouch. Too much!" Her poor, poor littermates! Didn't phase her a bit. 2) Redirect her attention with a toy. I throw a stick for her and she immediately chases it. But, just as often as not, she takes the stick (or toy or whatever) runs farther away, leaves it, runs back full blast and pounces on me.
The only thing that does work now after a bit of training is to say "Sit!" and hold a tiny treat out to her. She will immediately work for food, which is good. However, she will also abuse this and jump up and sit down with that expectant look on her face. Pure manipulation!
She is darling. I do hope she grows out of this biting phase soon, however.