When there are places to tie the ropes to, or to hook the bungee cords to , then it is easy to tie loads to car roofs with ropes or bungee cords
The places to tie the ropes, or hook the bungee cords , are w called anchor points.
Here is how to make these temporary anchor points
The use of a ratchet strap is also most highly recommended.
The use of a rubbery roof pad is also highly recomended
Step 1: Materials
The materials have to be strong and thin.
For my vehicle, I would consider strong as having a working load of 75 pounds or more
I would consider thin to be less than 3/8 inches thick.
Although I will illustrate the procedure with nylon military belts ( straps)
Other materials could have been used.
Cable Ties ( Zip Ties)
Other thin wirres or cables