Got a denial letter for unemployment, what now?

I got a denial letter last week saying I left my job voluntarily, but I was let go as a security officer. I do not usually post, so bear with me. I have not done a hearing before and I am nervous. If you have appealed before, what helped you prepare?

Legal aid offices and some workforce centres help with unemployment hearings at no cost. A call is worth it.

Keep everything in writing and save the confirmation numbers. It saved me later.