This week, starting last Saturday: Try to avoid having you and your child coming down with stomach diseases that makes you throw up what ever you may eat when going on vacation. Restaurant and airplane visits are not improved by being covered in puke.
Same time as above: When going on vacation to mother that you don't meet more then once a year, try to remember why this is so and brace yourself for the impact. Bring along clean underwear and a big bag of patience.
Same time as above: Know that even though you might get irritated over the people you are staying with for a week have a tendency to talk loudly and stay up late, you will have your revenge in the morning when your kid wakes up at 6:30 and starts playing the piano.