These are four key components needed to hit a draw:
- The elbows must fold correctly during the swing which enables you to release the club
- You must stay in your posture during the swing
- You must eliminate the sway on the backswing
- You must eliminate a slide forward in the downswing
There are probably several more items we could discuss in learning to hit a draw, but I think this drill covers the most important areas.
As far as an iron swing, the best drill is to hit shots with a mid-iron from a side hill lie with the ball above your feet. You can engrain the same feel from this drill as sitting in a chair with the driver.