Step 2: Locate the CD changer plug & Pins
Now here's where you have to do a bit of googling. Figure out what the pin layout is for your radio's CD changer. Try searching with something like "Honda Accord 1996 CD changer pinout" I was able to find this layout for an Acura which was close to my Honda for the basis of mine. Remember, there's only a couple car makers, so there's a lot of similar equipment out there across brands. Honda Civic may be close to the Accord, and also close to an Acura. The same should apply for domestic cars made by the same manufacturer.
The 3 pins you need are: