Always be sure to move your disabled vehicle to a safe location and far enough off the shoulder of the road to ensure personal safety.
I know it may sound trivial, but we should all have a small emergency kit in the trunk which may consist of blankets (including a white cloth to hang from a window or antennae), bottled water and some sort of reflective material such as flares and/or triangles. Once you’re in a safe place, call for help.
It’s always best to have your car routinely serviced, especially if you frequently travel. Make it a habit to have the spare tire inspected each time to ensure it will be functional should the need arise. You do not want to pull over due to a flat tire and you come to find your spare tire is useless as well.
If you are a motorist and come upon a disabled vehicle, remember it is state law to move over or slow down if you see an emergency vehicle pulled over to the side of the road with their emergency lights on. If you chose not to, you could face a large fine or far worse, a life or lives may be lost.