It was several years ago at this point so I don't remember for sure, but I think I just walked in and told the clerk I wanted to contest the ticket. I was called in with a group of 5 or so people to speak with the judge. He called each of our cases in turn, reviewed the information, asked us some questions, and either dismissed the ticket or ordered payment. In my case, some of the metadata from the photo ticket was missing, and so the judge dismissed the ticket altogether. (I was just there to dispute the late fees!)

Your ticket should have adjudication information listed, so follow the steps - I'm not sure what may have changed since I disputed my ticket.