Appeal deadline questions after an unemployment denial

I got a denial letter last week saying I left my job voluntarily, but I was let go as a retail manager. It has been weighing on me all week. I have not done a hearing before and I am nervous. If you have appealed before, what helped you prepare?

Thanks for writing this out. I went through something close to it 12 months ago, and it settled down once I kept a simple log of every call and form.

File the appeal before the deadline, even if you are unsure. You can gather documents afterwards. That is the one part I would not wait on.