An interview is not a dialogue. The whole point of the interview is to get the narrator to tell his or her story or to give you information. Limit your own remarks to a few pleasantries to break the ice, then ask brief questions.
Avoid dead-end questions; ask questions instead that require more of an answer than "yes" or "no." Start with "Why, how, where, what kind of . . ."
Ask one question at a time.
Ask brief questions.
Start with non-controversial questions. A good place to start with is the person's background. This allows you and your narrator to become comfortable, make eye contact, etc.
Don't let periods of silence fluster you. Give the person a chance to think of what he/she wants to add before you hustle into the next question.
Don't worry if your questions are not as beautifully phrased as you would like them to be for posterity. A few fumbled questions will help put your narrator at ease.
Don't interrupt a good story because you have thought of a question or because your narrator is straying from the planned outline. If the information is pertinent, let the person continue, but jot down your question so you will remember to ask it later.
If your narrator does stray into non-pertinent subjects, try to pull him/her back as quickly as possible. Example: "Before we move on, I'd like to find out . . ."
It is often hard for a narrator to describe persons. An easy way to begin is to ask him to describe the person's appearance.
Interviewing is one time when a negative approach can be more effective than a positive one. Ask about the negative aspects of a situation. Example: In asking about a person, do not begin with a glowing description. You will get a more lively answer if you start out in the negative. "Despite the mayor's reputation for good works, I hear he was a very difficult man for his immediate employees to get along with."
Try to establish at every important point in the story where the narrator was or what his or her role was in this event, in order to indicate how much is eye-witness information and how much based on reports of others. "Where were you at the time of the Oklahoma Bombing?"
Do not challenge accounts you think may be inaccurate. Instead, try to develop as much information as possible that can be used by later researchers in establishing what probably happened.
Do tactfully point out to your narrator that there is a different account or contradictory information of what he or she is describing, if there is.
Try to avoid "off the record" information, the times when your narrator asks you to turn off the recorder while he tells you a good story. Ask if you can you record the whole thing and promise that you will erase that portion if the narrator asks you to after further consideration. Then keep your promise.
Don't switch the recorder off and on. It is much better to waste a little tape on irrelevant material than to call attention to the tape recorder by a constant on-off operation.
Interviews usually work out better if there is no one present except the narrator and the interviewer.
Do end the interview at a reasonable time. An hour-and-a-half is probably maximum. First, you must protect your narrator against over-fatigue: second, you will be tired even if the narrator isn't.
Don't use the interview to show off your own knowledge, vocabulary, charm, or other abilities.