If you ego mind comes back in during the session, you have one of two choices. First, you can refocus your attention on the breath, making sure to follow the technique that you started with for several minutes (Deep, diaphragmatic breathing through the mouth, a little faster than normal, with no gaps or pauses). That will generally re-quiet the ego mind. Alternatively, look for what emotion is being brought up when your thoughts come back in. It may be frustration, or anger or disappointment. Amplify that emotion, visualize it spreading throughout your body, getting bigger and bigger, and make whatever loud sound your body wants to make for a period of time. That will almost always catapult you back deeply into your process.