How do you change plugs in a Buick lacrosse?

To change the spark plugs in a Buick Lacrosse, first, ensure the engine is cool and disconnect the negative battery cable. Remove the engine cover if necessary, then carefully disconnect the ignition coil connectors and remove the coils. Use a spark plug socket to unscrew the old plugs, then install the new plugs, ensuring they are torqued to the manufacturer's specifications. Reassemble the ignition coils, reconnect the battery, and start the engine to ensure everything is functioning correctly.