Spread the carbag flat on the ground. Undo the zippers.
Now, drive the car at the center of the bag, either front or rear first.
Once the car is parked squarely in the middle, close the zippers.
Roll the front end of the bag. Bring both edges together. Fasten the hooks then place on top of the car trunk so that no water will seep in.
Secure the two harnesses around the car. Affix it to a very steady and sturdy structure, such as a foundation post.