"What can I help with?"
Everyone has that moment when you get a phone call from Aunt Sally or one of your besties. They just got their invite in the mail and the question always comes up, "What can I help you with?". Whatever you do don't say nothing! The people that you invite to your big day want to be a part of it if they ask. Give them a simple job. You could have them setup a guestbook at the entry table, greet guest as they come in and let them know where to sit, or even just bring ice. You can never have too much ice. (Especially here in Texas) It is a small gesture that they can make and one less thing on your list to worry about.