I'll tell you. It's easy as sh!t, I did it.

The nossle itself has a little metal thing inside it that actually sprays the stuff.
That's on a bearing, so you can just stick a pen in there and point it up or down or left or right.

Point it straight up as far as you can or something and try it out.
Mine shoots about 6 feet behind the car.

I was on I-5 one time and a guy tailgated me, I sprayed him and he passed me laughing and giving me a thumbs up.

=]