The key to generating more power from the downswing is leading with your lower body, and there’s a tried and true method for honing this skill — the step drill.
After setting up normally, bring your lead foot and your trail foot together. Start to draw back the club as if you’re making a normal swing, then, as you start to make your turn, step forward with your lead foot. This will sequence the downswing, making it harder for your upper body to get ahead of the rest of your swing. You’ll start to generate more power from your lower body.