Everyone was different because during our fall training we all did the entire warmup together, when December rolled around we were doing warm ups on our own. We had to be ready to go at the time of the the workout. So we may have been together we were doing different things.
What I like to do is;
Prisoner Squats, Hyland Fling, Front Lunge, Side Lunge, and Speed Skaters. As far as form drills go it would depend on the type of workout. Intense days I would go with fast, quick form drills. On less intense days I go with A's and B's for sure and seated arm action, etc.
It really depends on the individual and what the individual likes and feels he/she benefits from the most.