Collar Choke From The Guard - Brazilian Jiu-Jitsu Techniques

Using your right hand to open your opponents collar slightly, use your left hand to grab the collar with your fingers on the inside (thumb outside). You don't have to get a very deep grip for this choke.

Slide your right hand inside the collar with your thumb on the inside (fingers outside). Try to get a deep grip with this hand.

Now pull your opponent down with your left hand and push your right elbow up to the ceiling.