How did the tire cracked?

Stop the car in a safe place
If noticed that the tires are flatDo not force to continue driving.
Hurry to park the car in a safe place and turn on the emergency immediately if possible.
Should park the car on the side of the road that is spacious and safe from traffic

Remove the necessary materials. before starting to change the tires.
Make sure that you have all the necessary materials, including spare tires.
The wrench that supports the jack and the flashlight without these materials.
Contact for help from an emergency insurance company

Use the jack to lift the car up
Bring the jack to place under the car near the flat rubber wheel.
Then use the jack to lift the car up until the flat rubber wheel floats out of the floor.

loosen the flat wheel screw .
By turning the wound wrenchLoosen the wheel nut until all relaxed.

Remove the flat rubber
When all the wheels have been releasedUse your hand to pull the tire that is flat from the wheel hub.

to install spare tires
Put the spare tires to the wheel hub and turn the wheel bolts tightly.
Then use the wrench to tighten the wheel tightly to the end.

Reduce the car
Use the jack to reduce the car until the spare parts touches the floor.
Then turn the wheel bolts tightly with the wrench again.

Fold the equipment and store in
When finished changing the spare tireFold the equipment and store in place.
Then drive to the nearest rubber repair shop to change to a new tire as soon as possible.