Inside and Outside
You may see, hear, or feel things within yourself or outside of yourself. Note each experience that arises as "In" or "Out." Your inner world of seeing or hearing thoughts and feeling emotions is called "In." The outer world of material objects, such as seeing, hearing or feeling your physical body or things in your environment, is "Out."
To do this technique, let anything arise in your awareness, determine if it is "In" or "Out," pay attention to just that for a second or two, drop it, and let the same thing or something else arise. Repeat this 3-to-5 second cycle for at least ten minutes, allowing each experience to arise and pass away freely.