To announce the big goings on at the circus many posters are printed handed out to folks and posted all about Rome. Problem is that the printing press will not be invented for many, many, more centuries. I am sure that the Romans were just REALLY ahead of the times.
I hate to burst your bubble, but the first plans for a printing press were made by Romans.
However, they were never actually put to any use, so I can see that a printing press wouldn't be used for this.
You said the flyers were distributed at the circus. It's the coliseum. Not the Circus Maximus. That's were they held chariot races. PLEASE correct me if I'm wrong.