There are a lot of important parts to a good golf swing.
It's close, but just ahead of a good grip, is balance. Without balance, a good grip won't help you too much.
As important as balance is, it's even easier to practice. You don't even need a golf ball.
Simply head to the backyard, or before you take the course next, and make some practice swings. Then, on your follow-through, hold it for three or four seconds.
This drill works best when you make an aggressive swing with a hybrid or an intermediate club.
Hold the follow-through and you'll start to develop the feel and control you have with your feet. If you can't hold the follow-through, make some adjustments with your feet and your swing until you can hold it.