I was already an employee with the company. My current supervisor recommended me for the supervisor position to go onto another team.
The interview was done at a Hiring Fair. At the time it was a closed-invite only hiring fair.
The interviewer had a sheet of questions to ask. Ultimately she was the one who would make the decision to hire/promote.
I had volunteer work on my resume. The interviewer liked that fact and actually was the only one who has ever pointed it out in all the years I have had that on my resume.