I'm hardly a vet yet either, but here's what I do:
Like Dave, I use the wheel, which I think is a fantastic invention. But it's not like you have time to check everybody every serve to see where they are in the rotation.
Mostly, I use it to track my setter and opposite.
I try to keep the numbers of the two who are front row in my head. So if blue's setter is 12 and her opposite is 7, and red's setter is 4 and opposite is 11, then on any given serve I'll note that 12 is back row, and 11 is back row. So I'm saying to myself, "7, 4. 7, 4. 7, 4."
It's really not all that useful to me when I'm R2. But it's good practice for me for when I'm R1. I don't have my wheel when I'm up, but I identify setter and opposite. Each serve I find my setter and opposite, and remember the numbers of the front row players. Then with each hit, I try to identify "front" or "back", saying the word in my mind.
Obviously at first, I'm identifying only one or two of the hits. But soon I begin to recognize who are the hitters that go with 12 and which go with 11. It's far from foolproof, but I feel like I'm starting to recognize alignments and identify hits as front or back row more frequently.
Don't know if any of that helps or not. I'm interested to learn what actual vets are doing
