Available races: Human, Quincy, Artificial Soul, Shinigami, Hollow, Arrancar, Vizard, Half-Hollow
When creating your character you must have these things present.
Those are the only requirements. However the more you add the better chances you have of getting a higher starting power level. Things that you may find helpful are pictures, brief histories of the character, and a role-playing sample. Your power level will be determined after you make your ability application.