As in any sport, your stature is going to affect how you play. A prevalent bad habit for tall golfers is moving the body too much while you swing. The solution for this issue is to set your body in a more solid position at address. You can accomplish this by bending more at your hips and tilting the spine forward. While you should have some knee flex, you shouldn’t feel like your knees are pushing downward.
One way to do this is by imitating the position you would use when lifting something heavy. Your lower body should feel like everything is pushing towards the center and up. Your arms should feel like they are hanging directly from the shoulders. Also, keep your stance on the narrow side. This will help minimize lateral motion and help you stay centered over the ball throughout the swing.
This solid position will help your swing be more aggressive and free without the body moving too much. During your swing, attempt to get your arm swing to match your body turn. One of the advantages of having long limbs is that it creates a wide swing arc, which gives huge potential for speed built in to your swing. However, the key is coordinating the movements of your limbs with the rotation of your body, which is why a solid stance is necessary.
Most importantly, what will help a tall golfer’s game the most is to make sure your clubs have been fitted correctly to you. While this seems like an obvious suggestion, most golfer’s issues stem from not having the correct size of clubs to work with. Here is a golf club fitting chart to double check the length of your clubs and make sure they are working right for you.