Since your audience views radio in their mind’s eye, ask yourself, “Where is the camera? What will be the audience’s point-of-view?” In a conversation between two people in a car, is the camera to their left or right? On the dashboard facing them? Between them, looking over their shoulders? In the back seat, listening from the passengers’ perspectives? Put your microphone where the camera would be, or mix the elements so that the listener is in that place.