These are some steps for changing tire.
First, turn on flash lights and safely pull off the road to a visible spot away from traffic. You can lift hood up to indicate other motorists about situation.
Apply the hand brake and put transmission in park or gear position.
You can get spare tire, leverage pipe, jack, lug-nut wrench from the trunk.
Make sure you chock the other wheels with rock or log to avoid car from rolling.
Some cars have hubcaps and remove it with screw driver.
You can use the lug-nut wrench to loosen lug nuts on the flat tire. After all nuts are loose, jack up the car and place jack vertically on the road. Put lug nuts in a safe place.
Replace flat tire with spare tire. Tighten the lug-nuts.
You can lower the car and remove jack.
Remove the chock and it is recommended to drive to a tire repair store.