I shorted out the electricity to half a house one day because I was exploring a request to change a light switch. After figuring out the fuse board which was installed by hippies (through sheer trial and error), I got the house lights back up but now had to fix this stupid shorted switch. Armed with rudimentary knowledge of electrical currents, I purchased a switch plus two bulbs from Home Depot, tried to read the instructions, got bored, and proceeded to “fix” the light switch. After I felt I had connected all the wires (cutting off some I felt were unnecessary and making structural changes to the wall), I turned on the power to the fuse, ran upstairs, and prayed to God I wouldn’t electrocute myself when I pressed the button.
This is how I learned to install a dimmer switch.