Toggle switch wiring

I tried browsing/searching all the forums to see if this had been covered as I thought it would be by now but I had no luck. I'm looking to wire up a toggle switch to my ic fan and just have it in one of the ports below and to the left of the steering wheel. Has anyone ever done this and have any tips? Thanks

bump. No one has done this and has any advice, or is this just way too obvious and I should know?

same basic principle for any fan or on/off electronic component.

wire up a relay for constant power, a switched power, and a ground. run the power output from the relay to the fan cutting into the existing power power of the fan. toggle the switch and the fan will turn on or off.