NOTE: Some cars have locking wheel bolts. If yours does, check your glove box for a special key. If you don't have this key, and have a lock -- you will not be able to remove your wheel.
If you are uncomfortable with changing your tire on the side of the road. Call for assistance - do not drive with a spare tire or punctured tire unless you have run flat tires.
Never raise a vehicle with people inside.
It is beneficial to practice this operation in your driveway so you can complete the task quickly and comfortable on the side of the road.
Check the pressure of your spare tire frequently (at least once a month) and before long trips. There's nothing worse than finding all you have to replace your flat tire with is... a flat tire.
Avoid products like "Fix-A-Flat" and alike. These make tire repair, if not impossible, much more difficult. Only use these as a last resort.
Step 1: Get to a Safe Location
Once you've come to a stop, make sure that you can safely open your door.