The center of gravity of your opponent is their hips, if you control the hips you control your opponent. Your center of gravity must be lower than theirs, drop your hips down below your opponent’s hips.
That’s when step number 2 “elevate the arm” comes in handy. When you elevate the arm the body follows, your opponent’s hips become higher than yours automatically, all you have to do is to drop a little bit especially if you are taller than your opponent.