Appeal deadline questions after an unemployment denial - first time posting

I got a denial letter last week saying I left my job voluntarily, but I was let go as an accountant. There are 13 people counting on me, so I am trying to be careful. The letter lists a deadline and a hearing process, but it is hard to follow. If you have appealed before, what helped you prepare?

Thanks for writing this out. I went through something close to it last year, and it got easier once I kept a simple log of every call and form.

Keep everything in writing and save the confirmation numbers. It made the follow-up calls so much easier.