Step 2...

Put the can in the footwell, with the part you will press facing the centre of the car because the spray will release at a slight angle.

Press the button so it sticks on, and close the door.

The can will run for about 5 minutes, once it has finished leave the car for a further 5 minutes, then turn off the car.
Use the cloths to wipe off the liquid as soon as possible, it will come off later with some cleaner, but it is better to wipe it off while it is still wet.
The car will smell of citrus for a day or so, but the result is aircon that doesn’t smell like Ghandi’s flip flops!!