These pictures should help you install the air kit. It is really pretty simple. Just direct the air to the outer edge of the sheave, the gap between the camplate and the outside of the primary sheave. I have seen customers install more than one air nozzle. 

To clean the sheave, start the engine, leave parking brake on. Place in neutral. Connect air hose and rev the engine up and down. This will cycle the sheaves without movement of the vehicle. Dust will flow out the air exhaust. 

If this is a new installation of weights and sliders, do not attach air to the air kit for 200 miles. You will blow the ceramic coating off your weights and sliders before they have a chance to transfer to the aluminum sheave.