Having organised a few now "Peaks Pootles"/"pooks pootles" whatever you want to call them, it's not that bad.
Just make sure everyone knows you aren't responsible for them, but be prepared to be able to advise on shortcuts etc.
Make sure you know the route.
As long as people who come on my rides enjoy them, I enjoy them, and I'll do anything to help people to enjoy it, even down to carrying two bikes up a hill once for a lad who was half dead.
Let people know –
route
meeting point
meeting time
departure time
type of riding
don't give them your phone number (i've found that people use you as a crutch as opposed to using their noggin)
It is fun, honest. My next one is on Saturday morning