Denied unemployment, how do I appeal? - 14 months and counting

My claim was denied after 15 weeks of waiting, and the letter says I have a short window to appeal. 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?

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