The main subject of the game is keeping the ball out of blue zone.
You need to try and hold the ball out of the blue field while holding the screen or not holding it at all. If the ball is white and you hold the screen the paddle will horizontally move to the left side, and if you stop holding it the paddle will move to the right side. If the ball becomes greens and you hold the screen it will move to the right side, and if you stop holding it the paddle will move to the left side.