One of the biggest differences between Tour Professionals and regular golfers is
the amount of attention the very best continually pay to their setup.

Rickie Fowler, in a instruction piece several years ago, made the point that he continually
worked on his grip, body alignment, stance width, and his posture (including the body bend and tilt)
in practice with his caddie. 

To view this short article on Rickie Fowler’s setup,

I think most golfers can embrace Jack Nicklaus’s comment that it’s almost impossible
to hit a good shot with a poor setup. So, the question is, why don’t golfers put more
effort into this relatively simple process? Which, of the several potential reasons
we’ve identified, do you think is the cause of so many poor shots on any given day?