F irst off, pack light. Next, pack all the things you will need in the evening of Day 1 in one bag. Keep your medals and other goodies in this bag, too. Again, this reduces the chance of something being forgotten. I'll tell you the magic word, but only if you promise to use it.
Sleep is a many splendored thing.
Try to get at least ten hours. Also, a bath can be very relaxing, as long as your hair is safe. Do not, under any circumstances, decide that it would be a good idea to run seven miles.