Not that hard but can be a little tricky.
First off play kick-off
Choose any club you like against other club.
Then choose difficulty amateur
Then try to get a corner, free kick or penalty against you. I will suggest to get a corner. After keeper catch the ball push R1 and X to throw the ball to your player.
Then try to score without getting interupted by AI or your own team. Score the goal and the trophy is yours.