Shown below is a picture of the headlight switch connector. Just unplug that from the old switch, as shown in the next picture. There isn't any secret clip that you have to undo or anything, it just unplugs. Sometimes it will be kind of tight and try to fight you a little bit, but, it will turn loose.
Next, pull the switch knob out, as if turning on the headlights.
There is a release button for the knob shaft on the switch, as indicated by the arrows. You can't see it with the switch installed in the car, but you can easily reach it, if you know where it is. This is where it is. You just push that button all the way in and, while holding it in, pull the knob shaft out of the switch.
Next, take a flat bladed screwdriver and unscrew the little bezel thingy from out of the switch.
Then the switch can be removed from the car. Place the new switch in the car, and re-install the little bezel thingy, insert the knob shaft into the new switch, while holding the release button down, and this is what you end up with. A brand new headlight switch installed in your car. When installing the knob shaft, be aware of the fact the shaft is triangular in shape, as is the hole that it goes into. Twist it around to get the shaft lined up correctly with the hole when re-installing the knob shaft. Don't use excessive force, because there are some things inside the switch that you can break. It takes a little force to get it in, but, don't start really leaning on it, or pounding it in with a hammer or something. It is a very simple job that you can easily do yourself successfully.