Move the joy stick left or right to change it. I'm guessing this is the part.

Go over the one you want to change, then hit A *like you said* You have the choice of making his power stronger or lower.

RMANPOWER

Go to the locker room, and there's a gym section near the costume selecting wardbrobe type thing. Go to the weight machine or treadmill (or whatever it is) and it will say customize attributes, then do it there.DJCaccy

From what I remember your experience points depend on the difficulty of your opponents AI. The higher it is, the more exp. Also, you get a smaller amount of points just for competing in a match, even if you do lose. Although if you bump the AI down to easy I can't see how its possible to have issues beating them, because its almost painfully easy at that point.

DJCaccy

But you can't do anything until you win. See, if you win matches THEN you can build up your stats because your player gets money from winning the matches.

If you're not winning matches then you're not going to be able to build up your stats ------> If you don't build up your stats, you don't win matches. It's a circular thing.