Two issues of my game that need addressing are:
1) Focusing on making my shot and not allowing cueball positioning to steal away shot accuracy.
2) I am standing up tooo early when taking my shot. My mentors continuously tell me to stay down when shooting, but I seem to have difficulty with this.
I am wondering about somehow incorporating these two aspects into the psr, so I might have a busy routine for a while until they become automatic.
1) Back up, and worry less about your end cue ball position, until you have a (very) comfortable shot making percentage. Or, at least drill only a few--or even only one--basic shot, and perform a PSR on that. Get your stance and basic strok sorted, and then review Dr. Dave's document (link in post by Bob Jewett), and focus on each step individually. You can start chaining them together as you go. It may also help, to say each step aloud, as you perform them.
As @gregcantrell suggested ("1-2-3") count your warm-up strokes (#6 in the Dr. D doc)--to which I would add, be conscious of the timing, with possibly a stress on the 3, as in 1-2-*3*, 1-2-*3*....a bit like a waltz. Also, practice a consistent speed/power--which is why it's better to drill only one shot setup (reduction of variables).
2) As others have suggested, you can focus on breathing, or count to yourself for help on staying down. However, I like to tell people to "watch the ball go into the pocket". In the case of a miss, it won't go in, but you won't know unless you watch it! This is also basically part of the "analysis phase" mentioned by Dr. D (and others), where you pay attention, so you can make your adjustments based on the results--it's a continual cycle of shoot-analyze-adjust (or test-measure-adjust, if you like). And since typing this has reminded me...you can also *listen* for the ball to drop into the pocket. --Stretch your concept of when a shot is completed, to cover the action that happens after you strike, and you should find that staying down *just happens*.--