If you want to join your friend on the same team while yuor playing , try not to tell you freind to stand right in front of you while your taking a goal kick. Because if you use full blast pointing the direction , your friend is standing then it will hit him sending the ball dircetly into the goal.

To score nearly every time from a corner, put the aiming bar as far right as possible then put the power up to just under half way. After the player taking the corner has finished his run-up keep pressing the directional button towards the goal and keep pressing square, this works nearly all the time: once you've mastered it!