There is no rule book for hosting shows. This is just a smattering of tips and things to think about that I've compiled over the years that could help the next show you host be a success.
What is your show about?
Type
First you have to decide what horses and disciplines you want to be featured in this show. Check and make sure there aren't a bunch of shows already being hosted in these areas, as people may not have time to enter both and will probably go with the one they saw first. The more specific your show is, the more unique it will be, but be sure it is not so specific that no one is qualified to enter. Common ones may be:
Experience