I already work at WFM and was applying for a team trainer position in my store within my department.
A few days before my interview, I received a document from the store team trainer (STT) detailing the team trainer interview process. The document discussed the project you need to complete and present during your interview, and a low-key due diligence process (not as involved as other leadership positions). In the days before the interview, I talked and/or met with store team leader (STL), department team leader (TL), other team trainers, and STT to learn about the role. I studied WFM's interview prep questions (on website), worked on project, and developed opening and closing statement.
Interview is small panel of 3-4 people (usually dept TL, STL, STT, Team member services personnel). The interview is organized as:
introductions
project presentation
opening statement
panel questions
closing statements
I was notified the same day that I got the job.