Players who tend to push the ball likely have an in to out swing path into impact. This is usually created by an over-active lower body, and a slower moving upper body. A great drill to help reduce your lower body movement is the leg together drill:
With a 7 iron on the driving range, place your feet together as shown in the picture and set up to the ball in the middle of your stance. Make full swings, while focusing on trying to keep your balance and turning your hips through impact. I cannot stress this enough, focus on the turning of your upper body… and the turning of your hips. If you can make solid swings, while turning your hips – you’ll help reduce your lower body movement, and start hitting straighter shots.
Also keep in mind the timing of your hips and your arm swing through impact. This drill helps with your swing tempo, balance, and upper body rotation. Give it a try!