It seems obvious that in order to hit great iron shots, you need to hit down on the ball and then take your divot. However, a lot of amateurs still have the shaft leaning back at impact.
The key idea for the iron swing is that the low point is 3-5 inches out in front of the ball, which is a difficult thing for people to do. Taking small swings, practice getting your hands in front of your lead leg, creating forward shaft lean.