Here's a look at the different pre-round practice routines of Phil Mickelson, Rory McIlroy and Stewart Cink:
During the practice rounds of the event (Monday, Tuesday and Wednesday) the Tour players will spend hours on the range and on the putting green. But here we see a much more deliberate and quicker paced routine.
I prefer to practice on the range with my long irons and driver, but only when I'm not playing a round. Before a round, I like to get a similar warmup of the various clubs and shots before I go out. Ben Hogan discussed how he would try to pick out some key shots on the course and then visualize himself hitting those shots on the range before a round and by the time he got to that key shot, he had already rehearsed it plenty of times.