Denied unemployment, how do I appeal? (update)

My claim was denied after 13 weeks of waiting, and the letter says I have a short window to appeal. Thank you in advance. The letter lists a deadline and a hearing process, but it is hard to follow. Did you bring documents or only talk?

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.