You need to be a Minor Arcana first. Either the Chalice, Sword, Wand, or Pentacle. As you progress in rank, you earn higher numbers. Once you hit a suit, you may test your mettle for for Major Arcana position.

See above by the red:

Every new recruit must start out as a 'Minor Arcana'. That is, they are assigned a Card Number Ace through King to one of four sets; Swords, Cups, Wands, and Pentacles. Upon achieving the rank of any face card, the character will be reviewed to become one of the Major Arcana Cards. All Minor Arcana take direct orders from any Major Arcana member, with theig Three' having final say over anything.