There are a number of excellent resources available to help you develop questions for your interviewee, some of which are posted below. Basically, you'll want to ask two types of questions: ones that elicit factual information about your interviewee, and then questions that will aid your narrator/interviewee in remembering specific events or circumstances.
Biographical data: Although you may have already obtained biographical information about your interviewee, it is standard practice to ask some of these questions at the beginning of the interview to help your interviewee get comfortable with the interview process and equipment. Don't forget to be sensitive to your interviewee's needs; some people are not comfortable disclosing their age or other personal information.
Open questions: As you get further into the interview your questions may begin to address more sensitive information. These typically include open questions, which means the questions cannot be answered simply with a yes or no, or other short response. Open questions probe for information and seek to trigger stories and memories from your interviewee. Examples include the typical journalistic questions of what, where, when, who, and how. They also may include phrases such as:
Try not to be too rigid with your questions. They are supposed to a jumping off point for your interviewee's stories and memories. Part of the value of oral histories is that stories often wander off topic to memories we would not have known to ask about and that greatly enrich the overall project.
Don't forget: Photographs, heirlooms and other objects can also help trigger memories. Invite your interviewee to bring any materials that might help them to explain or describe events.
Adapted from Oral History Toolkit, Claremont Colleges Library
Although there are many resources offering advice on conducting the oral history interview, the most concise resource is the Oral History Association's "Principles and Best Practices." The items below are excerpted from the OHA resource.
Both parties should agree to the approximate length of the interview in advance. The interviewer is responsible for assessing whether the narrator is becoming tired and at that point should ask if the latter wishes to continue. Although most interviews last one to two hours, if the narrator wishes to continue those wishes should be honored, if possible.
The Lead: Begin your interview recording with a “lead” at the beginning of each session to help focus your and the narrator’s thoughts to each session’s goals. The “lead” should consist of, at least, the names of narrator and interviewer, day and year of session, interview’s location, and proposed subject of the recording.
Along with asking creative and probing questions and listening to the answers to ask better follow-up questions, the interviewer should keep the following items in mind:
Adapted from Oral History Toolkit, Claremont Colleges Library
Thank your interviewee. You should spend time at the end of the interview, once the recorder is off, to relax a little bit with your interviewee and thank them for the opportunity to share their story. Additionally, it is a good idea to send a Thank You card to your narrator - not an email or text - so make sure you have a mailing address.