K.P.
I think you all should pick out a recipe, or few, and decide who does what, and everyone gets a list of things to bring, including, pans, pots, cutting knives etc, whatever they will need to do their part, and list what order you can do things. Such as if two of you are cooking, then the others are cutting or drinking wine ;)
It will make it easier on you and everyone does their own dishes so that no one does them all.
Keep it simple and organized! and clean up as you go so then it wont seem so messy.