If distance is your issue, lag might be your solution.
LAG BEHIND FOR MAMMOTH DRIVES
You're arrow-straight off the tee. Just one problem: Your arrow doesn't fly very far. You lack that oomph that your big-hitting buddies possess. If you want to go from bunter to bomber— and even blow it past your pals—you need more lag in your swing. Lag is the feeling that the clubhead is lagging behind your hands in the downswing before it "catches up" at impact. This whiplike movement is what lets long hitters deliver massive amounts of stored energy into the ball at the right moment. Here's how it's done.
To start, make your backswing as wide as you can. This width lets you maximize the amount of coiled energy you create. It also prevents you from straightening your right arm and releasing the clubhead too soon (a move that lets much of that energy dissipate before impact). As you swing the club back, try to keep your left arm parallel to the ground, and feel as though you're turning your chest to the sky. This helps you extend both arms, and it puts you in a powerful position at the top of your backswing.
Halfway down, try to return your left arm to the parallel position you achieved in the backswing, but this time bend your right arm so that your right elbow points at the ground. The more bend you have to your right arm on the downswing, the more speed you'll generate when the arm straightens through impact. You want to feel as though the elbow is being pulled down while your hips and upper body unwind toward the target. This keeps the clubhead lagging far behind the grip, producing an even bigger angle between your left forearm and the clubshaft. That's the narrow part of the "wide-narrow-wide" equation.
Finally, as your bent right elbow straightens and the angle is released through impact, both arms should extend powerfully out toward the target. The longer they stay straight, the more energy you'll transfer to the ball. This final wide position is akin to cracking a whip—and it's what produces that extra burst of power you need to bomb it past your buddies.
After impact, allow the momentum of the swing to pull both arms toward the target. You want full extension. The longer your arms stay straight, the longer your drives will be.