Common interview questions for a drafter would be about specialized classes you took (pertaining to the discipline of the company you're interviewing with) in college or training since, discussion about past job tasks or professional organizations you belong to.
Some companies administer CAD tests as a part of their interview process; since many people took A CAD class or two during high school and college and add it to their resume, even if they're not intimately familiar with it. Usually this will just entail running through some common commands with a sample drawing (creating layers, drawing different entities, using x-refs and plotting from paperspace).
My only real 'tip' would be that if you're new to the job market; only take in a serious set of prints/portfolio to display your skills, no intricately detailed anime figures. I've heard many people get disregarded because of something like that. Yes, it took skill, but, it's likely the interviewing manager doesn't realize how much skill and just sees a cartoon.