Here is a published list of helpful tips for interviewing. The credit is:
Jacqui Banaszynski, Nieman Conference on Narrative Journalism, March, 2008, Boston, MA
1. Know and state your purpose (for THIS interview)
2. Try to interview in their native habitat
3. Envision the ideal interview beforehand
4. Establish guidelines and negotiate terms early
5. Use props and contrivances as prompts
6. Help your partner – place her in a scene
7. For every question answered ask several more
8. Ask likely questions first – feared ones later
9. Don’t interrogate – be an interested listener
10. Follow up
In applying these general tips to interviews in writing another’s story, I must add that you really need to learn to listen empathically to encourage a deep and detailed interview. Listening is perhaps the most important thing in an interview.
For the purpose of writing another’s story, requiring much more involved interviewing than journalism reportage, number 9 just doesn’t quite cut it, I think. “Interest” is simply too superficial. You actually have to be involved. And I mean emotionally.
That’s the key to eliciting the kind of heartfelt emotion that will make your story more than just a travelogue. It also will provide the sort of color that you will need to capture a person’s character. Then your writing about that person will be truer and more vibrant to your readers–even the ones who know your writing partner personally.