Imagine you are sitting on a park bench. As people pass by you, notice them. For a time, allow them to become the center of your focus. Notice the older woman walking the small dog. Notice the young man jogging. Note their appearance and observe their behavior. For as long as they are in front of you, notice them. If two people are in front of you, notice both of them. Do not invite anyone over to your bench to sit down with you. Do not get up from your bench to walk with anyone. In as much as you engage them, you do so only from a distance. You observe them objectively from your bench. When they move on and are no longer in front of you, let them go and turn your attention to the next passerby.
The park bench experience is analogous to an exercise that can be done with your thoughts, feelings, physical sensations, and observations of the space around you. Imagine that the people in the park are your thoughts, feelings, etc. Sit quietly and allow yourself to become aware of your thoughts, feelings, sensations, and surroundings. At any given moment, whatever is the most prominent thought, feeling, sensation, or observation is the person in front of you in the park. Notice it and describe it. For as long as it is the most prominent object, give it your attention but do not engage with it. As it fades away, allow something else to have your attention. Do not chase after thoughts or sensations. Do not invite anything to sit with you. You are an objective observer. You notice but do not engage.