Don't follow the ball when setting the field and get people to do stuff like collecting teas, sight screens and boundary rope for you and have fun!
As above, at our level (Sunday friendly biff) we get a fair few people whose playing experience is limited and are there for the social aspect and to get involved. It's always been big thing for me to get everyone who's in the 11 to do something, on and off the field. They will feel like they've contributed, that they've got something for their money and they'll more than likely want to come back.
Make sure you listen to others too, I don't know where you normally field but someone else will always see something you've missed. Above anything make sure you enjoy it, in a certain sense it's made me calmer as a batsman and not throw my wicket away as often.
I'm sure you'll have a few equally experienced cricket brains to help you out there on the field.