It doesn't sound like you are training for a PL meet so why would you think the best results would come from doing them all the same day?
If you do 3 workouts a week start each workout with one and go through to max.
Or, try one each Monday for 3 weeks.
Well about warmups.
10 min cardio or something to get the blood flowing
Do 10 reps of what you could do 20
Do 6-8 reps of what you could do 12-15
do 3-5 reps of what you could do 8-10
keep tight--good form--feel it-prepare your mind
then I like to do 1 rep at about 85% max. You know you can do it but it just seems neurologically better than the big jump from say 200 to 300. You pop in that 1 rep at 265 or so.
Wait 2-3 minutes and put 5 more lbs on the bar than you think