Yeah, the process a bit weired.
People goes there to register.
But you will have to try logging in to create the new account.
So, fill up the box for your mail address and password (same as you use in world1)
And from the box select World 2.
Then click log in.
They will take you to another page, where you will have to choose the desired username for you world 2 account.
Choose the nick and then wait for the 1st of August.