You need to have the key and turn it to the on position (disconnect battery first) and then find and push the little button on the side of the switch unit itself. I believe it is in the 7 or 8 o'clock position if I remember correctly. Push in the button and extract the cylinder. It's a bit hard to locate as it's behind the dash and you usually cannot remove the switch unit without pulling the key cylinder first. I make a little tool out of coat hanger wire with a small bend in the end and feel for it. Laying on your back with the seat out, using a magnetic flashlight and having a transparent hand can help. ;)