Raise the car as high as possible.
In the fuel tank filler neck, lower the hose to the bottom of the tank. If necessary, use a piece of garden hose.
Lift the hose with the top opening upwards and then close it with your finger. The receiving container should be placed significantly below the level of the bottom of the fuel tank. Now lower the closed end of the hose into the container. Quickly remove your finger: if the end of the hose in the fuel tank is still in gasoline, then the fuel will flow at the speed of falling from the fuel tank. If not, repeat the procedure.
Warning: Sucking fuel with your mouth can be dangerous to your health.
If the fuel tank is not full enough and your receiver remains dry, then use a suitable hand pump.