This advice is perfect, but doesn't work for all kittens unfortunately. *I
had one who just had to bite, so I made him a biting mitt which was just an
old t-shirt rolled up tightly. *We had to teach him to only bite it and it
worked.

While this might work for you, I would not recommend doing this. It's
easy for the kitten to get confused or very playful--and you could get
bitten when you're not expecting it.

I'd stick with the OW or NO very loudly. Let your arm/hand go limp
(pulling it away encourages more biting), and slowly walk away. He'll
soon learn that biting means no more playtime.

Also, do NOT use your hands or toes to play with him. Always use a
toy. If you anticipate being bitten (for instance, if he usually bites
your toes when you walk into the bathroom), take a toy along and throw
it to disrupt the behavior.

Be consistent and make sure everyone the household does this. Your
kitty is at a critical age and is learning what is good manners.