Sure, pull-aparts are nice, but they're not the panacea that Defranco claims.
When I first starting lifting, I usually just warmed-up by doing light sets before getting down to work. Now that I'm an old-ass 31 years of age, I need a little bit more. I came up with this warm-up routine and I think that it works very well. Should only take about five minutes.
1) Band pull-aparts. Popularized by trainer Joe Defranco, the pull-apart is pretty self-explanatory. Buy some cheap exercise bands and pull them apart in front of your face. This will warm up your upper back and shoulders. Do 20 reps.
2) Band curls and pull-downs. Elbow tendenosis is a problem for many lifters. Get blood flowing to that region by doing some simple arm work. 15 reps of each exercise per arm.
3) Lat stretches. Grab a hold of your power rack and stretch. Hold for at least 20 seconds.
4) Plank. Lie down on your elbows and tippy-toes. Hold for 60 seconds. Warms up your torso, which is important for any compound lift.
5) Quad stretch. Grab your foot and pull it to your ass. Hold for 20 seconds.
6) Hamstring stretch. Keeping your legs straight, bend down and touch your toes. Hold for 20.
7) Leg swings. Swing your leg out side-ways while keeping it straight. This really warms up your hip flexors, which will keep you from pulling them while you're squatting. Do 20 reps (I like the number 20).
8) Glute stretch. Lie down on a bench and pull your knee to your torso. This stretches your glutes and your hips.
That's about it. In between sets, I'll do a few of these exercises to keep blood flowing. Warming-up ensures that you'll be loose and frisky for your heavy sets.