How do you remove a broken key in a ignition switch?

Try going to a hardware store & buying a coping saw blade {it looks like a piece of wire with a spiral cut running down it} cut the end off the blade and with the ignition turned to the place where you would pull the key out, slide the wire of the blade in next to the key and gently slide it out.... the spiral cut in the blade should grab the key and pull it along with the blade.... if that doesn't work you may need to see a locksmith.