You're not ready for multiplayer yet.
Revealed at the E3 2011 press conference, the multiplayer in Kid Icarus: Uprising features three-on-three combat. Each side plays as a generic character that controls the same way as Pit does in the single-player. The goal is to defeat the members of the other team until an angel appears. After the angel appears on your opponent's side, your goal is to defeat it.
The controls for Kid Icarus: Uprising are passable in the single-player, but in the multiplayer, maneuvering with the Circle Pad and the stylus is extremely tough, as the action is fast paced. Basically, the steep learning curve for the regular control scheme is multiplied in the multiplayer, especially since it's not a linear experience.
One thing that is cool about the multiplayer is the layer of customization with the weapons. Like the single-player mode, you have a variety of weapons to choose from, each with different powers and attributes. One time, I used the bulky arm cannon, which slowed me down considerably, but gave me some great weapons.
The multiplayer doesn't seem to be too great, at least from what they've shown so far. The controls work in the single-player because it is more or less linear. Naturally, the arena battling mode isn't linear, so fine-tuned movement is a chore.