The button instructions are assuming you have the default settings. Simply start a Kick Off game on an easy difficulty (I did this on the Beginner difficulty). Run towards the wing whilst dribbling the ball, then click L3 + R3 to start the Player Lock. Flick the Right Stick in the direction of your player in support and click Square to cross the ball to you. Shoot with Circle and upon scoring you will have your trophy.
I created this video to help:
Hope this helps.