You just have to wedge a small screwdriver on the sides and rock the switch out. The steering wheel is rubber and it will return to its normal shape. The hard part is unplugging the little wiring harness. The wire is so short it's hard to pull the button out far enough to get in there to unplug it. Once it is free from the steering wheel, you don't want to pull it too far out or you might break the wire.
Alternately, others have pulled the entire steering wheel off. Apparently there's a "back way" in but you'll need a steering wheel puller tool for that.