Banana Shoot:
Press Square for power and then press Cross then Circle then the direction you want the ball to turn. e.g. In corner kick, press square 3/4 power cross, circle, press Left/Right.

Small Curve:
Use it only when you're 1 on 1 with the goalkeeper. When you see the goalkeeper run toward your player, tap Square then quickly press L1. Guaranted 99% goal if you do it at the right time.