Park the car in a safe location: This should be on a level and stable surface, away from traffic. Engage the parking brake and turn on the hazard lights.
Locate the spare tire and tools: The spare tire and tools should be located in the trunk of the car.
Jack up the car: Use the jack provided in the tool kit to raise the affected side of the car off the ground. Make sure to place the jack on the proper jacking point, as indicated in the car's owner manual.
Loosen the lug nuts: Use the lug wrench to loosen the lug nuts on the affected wheel. Do not remove them completely at this point.
Place the chock: Place the chock behind the wheel that is diagonally opposite the flat tire. This helps prevent the car from rolling while you're changing the tire.
Jack up the car further: Jack up the car until the flat tire is about six inches off the ground.
Remove the lug nuts: Completely remove the lug nuts and take off the flat tire.
Mount the spare tire: Place the spare tire on the lug bolts and secure it with the lug nuts. Tighten the lug nuts by hand as much as you can.
Lower the car: Jack the car down until the spare tire is touching the ground.
Tighten the lug nuts: Use the lug wrench to tighten the lug nuts in a star pattern, alternating between opposite lug nuts. Tighten them to the recommended torque, which is typically specified in the car's owner manual.
Lower the car completely: Lower the car all the way to the ground.
Put away the tools and spare tire: Place the spare tire and tools back in the trunk of the car.
Drive slowly to a tire shop: The spare tire is typically meant for temporary use, so it is important to drive slowly and avoid sudden maneuvers. Get to a tire shop as soon as possible to have the flat tire repaired or replaced.
Remember to always follow the specific instructions outlined in your car's owner manual for changing a tire, as there may be variations in the steps depending on the exact model and year of your BMW.
