KEEP IN MIND: The ball is not the enemy, and the equipment is there to help you. A lot of young catchers forget that all the extra padding and equipment is there for their benefit, not just to look good. If coaches constantly reminded young catchers that they can use the equipment to help them get better, then catching would be a lot easier.
COMMON PROBLEMS: From what I see, the most common problem with stopping the ball is a young catcher's habit of turning his shoulder away. It's a lot like hitting. They don't want to get hit by the ball, so when it goes awry, they turn their bodies. Well, that does two things. It negates the whole purpose of the equipment, and it also puts you off balance to make a recovery.
THE KEY: At all times, the goal is to keep the ball in front of you. So the chin guards and chest pads are there not just for protection but as an added defensive tool to help keep the ball in front. Young catchers must learn to use them. Coaches should practice throwing those soft baseballs at the catchers and make them stop the ball with their bodies. No glove work at first. Just stand a few feet in front of them and force them to stop the ball with their pads, chest protector, boots, whatever ... no glove.