To work on taking a proper approach on a ground ball, place cones in an arc in the outfield.

The semi-circle represents the necessary angle to take in order to be moving towards the target when fielding a ground ball.

Again, work first on the concept of taking an angle (surrounding the baseball, similar to a fielding approach) and then add the fundamental steps of fielding a ground ball in the outfield.

For more information, check out my book Coaching the Beginning Pitcher.