From Lyle McDonald's warming up for the weight room: 1) Do whatever cardio you prefer at an intensity that brings on pre sweating clamminess (where you're warm enough to start sweating but not actively 'beading', I usually row or do an incline speed march) 2) Do lift specific mobility drills/empty bar work if necessary (I sometimes tit about with an empty oly bar if I'm going to be doing 'heavy' C&J/OHP/Push Press, more often than not for squats I'll do hip openening/glute activation drills/stretches with some dislocations/round the worlds with a lightweight bar for shoulder/chest stretch)  3) 2-3 reps @ 65% working weight super slow 4) Ramp or jump to work sets depending on you. That said, I don't really do warm up cardio, I have to go up some stairs to the lockers, back down them, do my mobility drills, set up the power rack after throwing some swagbro doing curls out of it (Seriously, get out the rack if you're going to curl the bar with 5lb plates on either end when their is a girl smaller than you throwing 45s above her head on the other side of the room)  - couple of 10 second pause squats at half my working weight and ramp up over 3 warm up sets (tonight I was doing something at 105kg, so pause squat at 80kg, double at  90kg, double at 100kg, double at 105kg, 3 minute break and away with the main work out).