Instructions
Load your game or begin a new game. You receive Lunamon as a beginning character, but if you have been playing for a while you may have moved Lunamon out of your party. Bring Lunamon back into your party using the in-game menus.
Explore the game world by walking around and getting into battles. Use Lunamon as much as you can in fights. This will earn her experience, as well as increase her friendship level.
Repeat until your Lunamon reaches Level 19. You can view your Lunamon's progress on the "Status" screen. While you are looking, also check the "Friendship" level. It needs at least 50 percent friendship.
Leave your Lunamon in the Digimon Farm to increase his friendship level. Explore the world while she is in the farm to increase her friendship level. When the level is 50 percent (you will need to check periodically), your Digimon has two prerequisites for digivolving.
Travel to a dark area and fight dark Digimon to increase your Lunamon's dark experience. You can also check this on the Status screen, and she needs at least 330 dark experience points in order to digivolve.
Repeat steps 3 and 4 to raise Lunamon to Level 19, 330 Dark experience and 50 percent friendship. When all three criteria are met, your Digimon will Digivolve.