How do you change headlight bulb 07 Cadillac DTS?

To change the headlight bulb on a 2007 Cadillac DTS, first, open the hood and locate the headlight assembly. Disconnect the electrical connector from the back of the headlight bulb, then twist and remove the bulb socket. Replace the old bulb with a new one, ensuring not to touch the glass part of the bulb with your fingers, as oil can cause it to fail. Finally, reattach the socket and electrical connector, and test the new bulb before closing the hood.