How to change spark plug in 2003 mercury?

To change the spark plugs in a 2003 Mercury, first, ensure the engine is cool and disconnect the negative battery terminal. Remove any necessary components to access the spark plugs, such as the ignition coils or covers. Use a spark plug socket and ratchet to unscrew the old plugs, and then install the new plugs, ensuring they are properly gapped according to specifications. Finally, reconnect everything and the battery terminal before starting the engine.