You connect your hose to the bottle and spray it over the car. It works ok, I have it. Are you sure you have not brought a refill bottle, or the Jet Wash version!
The main bottle for the hose looks like this; (when you buy this version, the hose adapter is at the back of the bottle, you just unscrew the cap and screw the adapter in its place)
I used this stuff today, worked really well. It is designed to run off and as it does it lifts dirt off with it.
In their instructional video it seems to hold onto the surface pretty well, ideally you want it to sit for a while before rinsing off so it has time to penetrate the dirt. With my regular pressure garden hose it just ran off the surface before it had time to loosen any dirt.....it did smell absolutely gorgeous though!!