help needed

ok so i have a train horn, a 1/4 hp air compressure, a 3 gal tank, an isolator and a pressure switch..... im having trouble trying to figure out how to wire up the isolator and the pressure switch to control the compressure.... can somebody maybe draw me up a diagram on how to wire this up to function correctly.....
here is the isolator i have and can't figure out how to wire correctly

here is my tank and compressor set-up

here are the horns under the hood

the thick red wire goes to your battery, the green wire goes to either one of the two wires on your pressure switch (it doesnt matter) The OTHER wire on the pressure switch needs to be grounded , the yellow wire on the isolator goes to switched 12V+ from your key, and the other big lug on it (the one with no wire) will go to your compressor power wire.

Try this link...same solenid as your using.