Use choke holds to cut off blood to the opponent's brain by pushing on the carotid artery and rendering him unconscious. Choke holds may result in death if done too forcefully or held too long, so people learning how to perform them should seek expert guidance.
For a front choke, grab the opponent's shirt collar with your dominant hand so you are grasping the collar with the back of your hand against his neck. Cross your other arm underneath your dominant arm, and grab the opponent's other collar. Pull the collar tight, pressing your dominant hand into the opponent's carotid artery.
The side choke begins with blocking the opponent's punch. Parry his arm inward, and put your dominant arm under his arm and against his neck, just below his ear. Wrap your other arm behind his neck, and clasp your hands together to continue pushing your dominant forearm into his carotid artery.
Perform the rear choke hold while taking an opponent to the ground. From behind the opponent, reach your dominant arm over his shoulder, and hook your elbow around his neck. Clasp your hands, and use your non-dominant arm to pull your elbow tighter and put pressure on the sides of the opponent's neck.