In this video I show a pretty cool submission off of a controlling grip from Side Control. This was a grip I was taught as a white belt but I never knew that it had any type of choke attached to it.
Wrist orientation, shoulder placement and aligning your forearm in the middle of the chest are all super important. Writing descriptions for these things would be very difficult so I highly recommend watching the video.
I can tell you that the pressure with your shoulder is very important. This is going to take some repping to maintain your balance. With that being said, I cant remember the last time I lost position or got reversed off of this submission attempt.