Kitten advice needed

A "gentle" pop in the forehead with the first 2 fingers is what I do to curb biting.

With discipline the important thing to remember is it has got to be immediate.
(in fact, still in the act is much better)

There's no time to go get a rolled up paper to swat.

By the time you get back, they have forgotten what they did and will think you're just being mean to them.