Edit Your Players!
At the
EA sports screen press A, B, A, B, B, B, A, and then Z. You will then be
able to change the colors of Fifa and edit the players.
Cool sounds
When you are playing in a match, if you press in any direction on the control pad, the crowd will "BOO" the other team. I like to do it when the other team scores a goal.
After you score a goal, experament with the C-buttons to make sounds like the other FIFA games.