Tip of the day

Since he will have to deal with the fallout of not being organised, put the onus on him. Tell him once that he needs to make a list and get it all done before he goes. If he doesn't do anything stay out if it - bite your tongue if you have to. If he brings it up - and as the time gets closer it's a good bet he will, just remind him casually that he had better start getting ready. In the meantime, make your own list (which will undoubtedly be more comprehensive than his) and if he breaks down and asks for help give him your list and tell him to get on with it.