What is the first step to execute a full mount stall?

The first step in executing a full mount stall involves sitting up and grabbing the subject's upper body. This action allows for better control over the subject while establishing stability in the position. By securing the upper body, the officer can effectively manage the subject's movements and prevent them from escaping or countering the position. This foundational movement is critical as it sets the stage for further control tactics that can be employed once the full mount is established. Properly gripping the upper body also helps in maintaining balance, which is essential for maintaining a dominant position.