Instructions
Start or load a saved game on "Yu-Gi-Oh!: The Sacred Cards." To reach deck capacity, you will more than likely need a few five, six, or even seven level cards to insert into your deck.
Press the "A" button on "Edit Deck" from the menu. A list of your collected cards will appear.
Press the "A" button twice on the card you want add to your deck. The stronger the card, the more it will add against your deck capacity level; however, only monster cards will count against the deck capacity level.