How do you get to kitsune?

If you mean, "How do I become a kitsune?" then the answer is that you can't unless another kitsune or deity transforms you into one.

If you mean, "How do I find a kitsune?" then the answer is probably a one in a million chance mixed with a ridiculous amount of luck that you'll ever hope to find one that isn't well disguised by illusion nor avoiding public scrutiny.