How do I defend the armbar from guard?

The armbar from guard defense has multiple stages, and the earlier you address it, the easier the defense. Prevention comes from maintaining good posture in guard and keeping your elbows close to your body. If they break your posture and start climbing their hips high for the armbar, immediately posture up and pull your elbow back. If they manage to swing their leg over your head, the hitchhiker escape involves turning your thumb up and rotating your body toward your trapped hand. The stack escape involves driving forward, putting pressure on them, and walking around to the side while keeping your arm connected. Clasp your hands together to prevent them from extending your arm. The key detail is to never let your arm be fully extended, which means keeping your elbow bent and clasped hands throughout the escape. Advanced defenses include anticipating the armbar and passing guard as they attempt it, turning the defense into an offense.