I really like to set up the brabo choke from knee on belly, but can't find an instructional that teaches my particular set up. It's quite easy to explain, though:
1. I've got KOB on my opponent's right side. As my opponent turns into me to recover guard or get to his knees, I reach across and pull his top elbow across his body (using my left hand against his left elbow), quickly dropping my chest on his triceps to keep the arm trapped.
2. As soon as I've dropped my chest on his arm, my left hand reaches for his head securing the so-called 'howdy' (silly internet name) position. At this point I'm using my chest on his triceps to turn his upper body towards me, while the knee on the belly - going straight across the hips - can keep his lower body flat if needed, creating spinal torsion and bio-mechanical weakness in my opponent.
3. Having secured my set up position, I take my right arm and dig underneath his armpit, shooting it all the way through (I drop my ear to his shoulder to get deep enough) until the right hand can grab the back of his head. Having secured head control with my right hand, I now release his head with my left and pass my left arm over his head, basing with the hand on the mat if necessary. I then use my elbow against the crown/back of his head to break his posture further, sinking my choking arm as deeply as possible until I'm able to lock a good RNC grip. Once the grip is in place, I simply drop my hips, shrug my shoulder blades back (most people tap at this point), and if necessary, turn towards the legs and ultimately finish from mount with my head on the mat.
In reality, this is a very simple set up, I just prefer a high level of detail when describing techniques in writing.