How old of a kitten? Like puppies, they play...and their baby teeth are exceptionately sharp...and they like to play rough. One thing if it's still tiny, just get up and walk away, or pull out a toy to distract....NEVER play back....by the time it's 4 or 5 months old, the game gets very rough....so don't start a habit that might be hard to break.
Yeah, they like to chew on stuff. I usually say, ow, no and tap her on the nose. I mean tap not hit (it isnt enough to actually hurt, just get her teeth off). My cat now knows how hard she can bite and that ow means back off. And yeah, just dont engage after that and she'll learn that play time stops when she starts to bite.
Depending how old. Once it gets to about a year, start biting it back. Not too hard, but enough to let it know, "oh, this doesn't feel good", but you don't want to hurt it. Best of luck
Same question, btw, more answers: http://www.funadvice.com/q/howdoistopmykittenfrom_biting
The kitten is a bit older than 6 weeks.