They must set the agenda, and not the teacher. This requires huge efforts on the part of the typical instructor. She must consciously take a back seat and be willing to learn from her students. She must be unusually well-informed in her subject area, to be prepared to interact fruitfully when students bring up issues apparently unrelated to the subject matter. There are lots of learners, they must be heard.
Much silence is necessary.
Dialoguers must listen well and this requires the cultivation of silence. The dead spots in a dialogue may be the moments when most of the learning is taking place. Dialoguers do not interview, nor do they debate. The interviewer merely questions, and the teacher who merely asks questions may give the appearance of hiding knowledge or of being disinterested. In a genuine dialogue, everyone questions and everyone answers.