1. Tap the Edit button

2. Change the order
You can change the order of the decks by dragging the icons on the right end of each row up and down.

3. Tap the Done button

Tutorial
Deck
How to register a deck
How to edit a deck
How to delete a deck
How to chenge the order of the deck
Card
How to manage your cards
How to add a card
How to delete a card