You can score easy goals by crossing from the side and pressing X for a bicycle kick/header (90% success rate).

Swap sides and sabotage your opponent's line up. Take off the king-pins, put center backs up front, etc. Then, resume control of your original team again and continue playing.

Move the C-stick slightly towards you then immediately press X. You will be able to score a beautiful goal from about 30 meters with some nice action.