Andreh Anderson is a black belt under Rey Diego at (www.reydiogo.com). Here he demonstrates a choke from side control that he learned from Rey Diego.
Start in side control with your right arm blocking his hip.
Another view.
Next, if your lapel/skirt on your right side is out of the belt, grab it. If not, remove it from the belt and grab the end so that the tip is pointing upward.
The ninja part comes in when your opponent pushes your head to make space.
When your opponent pushes, bring that lapel out from the side and feed it to the hand under his head.
Feeding the lapel/skirt to the hand.
Ready to move into the position to choke.
Move your body toward north/south and use your head to block his right hip. He should already start to feel pressure.
The final position. Tripod up and walk toward his head. The more you cross toward his head, the tighter the choke gets.