Denied unemployment, how do I appeal? - what worked for you?

I got a denial letter last week saying I left my job voluntarily, but I was let go as a welding apprentice. I am in Salt Lake City, in case local advice matters. I have not done a hearing before and I am nervous. If you have appealed before, what helped you prepare?

Stay calm and stick to facts. Mine lasted about thirty minutes and felt more like a conversation than a trial.

I printed my emails in order and wrote a one-page timeline. The hearing officer kept going back to it.