If vacation-time means a road trip, a few simple preparations can keep you safe and out of trouble. Check all fluids, including oil, coolant, brake fluid and windshield washer fluid. Check the air filter and battery.
Make sure tires are properly inflated. That goes for the spare, too. Inspect the tires to make sure there is enough tread. Besides the obvious safety issues, proper lights and signals are just one more reason why you won’t get a ticket.
At an absolute minimum, make sure you have the tools to change a tire. But also consider carrying a battery-powered cell phone charger, drinking water, a gas can, and a working flashlight.
Do you have a spare key accessible from outside the car? What about jumper cables? A bowl so that Fido can have a drink? How about a rain poncho?
Take your license, proof of insurance and registration.