Developing a Foundation of solid Swing Mechanics at a Young Age clearly gives a player the most potential for success in the long run. The earlier you're able to identify and correct critical mistakes, the less. Unfortunately, many players wait until it's too late and are unable correct mistakes that are ingrained into their swing. Address them now, before it's too late!
Using the body and arms together in correct sequence and not simply swing with the arms
Prevent "casting" the hands and arms away from the body at the start of the swing
Learn to take the hands on a direct inside path to the ball