The Trinary switch will have 4 short wires coming out of it, the color of the wires can vary from switch to switch depending on the manufacture of switch.
Normally you will have two blue, with or without a color tracer (electric fan circuit) and two black, with or without a color tracer (compressor circuit).

Installing and wiring a Trinary switch

Once you determine what two wires are for each circuit, you can start wiring.