On the EU side Odin is a server that is often closed of an afternoon/evening time, however I it is open for creation of new characters in the morning time. I would expect Balmung will be similar. Choose a quiet off peak hour. If it's a problem for them accessing the game for long enough to create a character at that time, just go through the character creation process as far as accepting the look and save the look. Then it's just a matter of loading the look and completing the class, location and name choices.

(I made a char on ever EU server at one point, before deciding which to play on. lol)