Some practical, some not so much...
~ Pack each child their own "snack kit" in a lunchbox or a bag. It's a great way to make them feel special and to keep the snacks at their fingertips. It's also a great way to keep your 3 year old from opening every granola bar in the box and eating precisely half of each one.
~ Flat tires can happen to anybody. Always carry a few quarters with you in case you need to pay for air after the gas station is closed. They also make very handy tire gauges with magnets on the back of them so that they will stay where you put them. (Just make sure that where you put them isn't too close to your ear while you're wearing earrings. The whole silver hoop, red tire gauge look hasn't quite come in vogue yet.)
~ When taking pictures at family gatherings, check your background! Nothing is as disappointing as hearing, "Wow! That's a great picture of Aaron...in front of that bright yellow port-a-potty."
~ If your car doesn't have air conditioning, bring along a spray bottle full of ice. As it melts, you can take turns squirting the kids (and yourself) for a little relief.
~ And last, but not least, if you do any shopping on vacation, remember that shirts with smocking tend to run a size smaller. If you don't believe me, that's fine, but make sure you take someone along with you to help you pull the shirt off your head when you get it irreversibly stuck around your elbows. (And again, thank you Mamaw. I doubt you thought you'd have to undress me at this age.)