how do i sign up for kms?

If you intend to just abandon it after a week, then no, you shouldn't even bother starting an account there. If you want to play to get content before everybody else, and continue to get content before everybody else, I think it's fine.

And if you're Korean, there's no reason for you to need the guide. It's not like they're withholding it because of that. It's for some reason nobody really knows.