I know that my club hosts foil competitions I think once a month, (i'm sabre) but I don't know how thoughs go. We also have intermurals for little kids to learn about competitive fencing and there are a lot of them.
Have food ready to buy, make sure a lot of people are going to come because it wouldn't be as exciting or fun. umm... I guess just do it as a real tournament. See how this one goes and then you can make and add changes for the next one.
I hope this answered your questions
