To feel the sensation of weight shift i suggest you try Gregs walking drill. Going by your post i think you are sliding and sticking a shaft or your umbrella in the ground behind your right foot (right hander) you will find this out very quickly. Make sure you turn your shoulders, pretend the ball is your pivot point on the way back your left shoulder should be pointing at it when you reach the top of your backswing and on the downswing drive your right shoulder at the target. I was struggling to brek 80 two weeks ago until the only thought i put in my head was to drive the right shoulder at the ball and through to the target your lower body will do everything else naturally.