This is a fun drill for anyone that has a full-length mirror and smaller plastic bat at home! I won’t bother to explain it – the video does a great job of it. Make sure they’re staying down over top of the ball, which is very obvious by where their weight is throughout their swing. If they’re finishing on their heels, they are letting their front shoulder pull out too early, and/or standing up as they swing.
Stay down, weight forward, hit dingers.