How to register for JP client?

[ZeraStar]

ok so i got a little impatient waiting for the EN server so thought i would check out the JP server. i got it to DL and instal just fine it starts upp just fine. even checked if my account worked on both sites (wich it did) however im confused on how i actually log in and create an account for the server itself. as the announcment a long time ago said only the site accounts are linked and not the servers. so could someone explain to me how i create an account on the JP server? step by step if you could.