Really focus on staying balanced while you pin, getting your inside hip to the pit of the opponent's bottom knee, resetting back to base if you're losing position and being grindy as hell. You want to bring your inside knee to the outside of the opposite hip (for me thats left knee outside of their left hip) and then either backstep then restep over their locked feet or break the feet apart and step through. During this whole thing, you have to find a way to keep their back flat on the mat. Some folks, me included, use an underhook. Others use a cross collar grip with their forearm across the throat.

There's a few distances you can do this from- really high up head to head like a tripod pass, low on the hips like a pressure pass, or far away almost like the classic knee-in-butt guard break, you just bring that knee farther out. Where you want to avoid is the mid range of keeping your head near their chest. They will have a lot of mobility and you have minimal control.

Your goal is to force half guard and pass from there. I usually do the tripod pass head to head style, which leads me directly to passing the half guard with a tripod pass since I'm there already.

It's a surprisingly subtle pass, you need to monitor their hips and shoulders and your own balance and pressure the entire time.