give reg number to motor factors who will supply the correct oil & filter, jack car up onto axle stands, take drain plug off, and drain old oil into suitable container, take old filter off, put a smear of oil around filter seal, fit new filter only needs to be hand tight,, refit drain plug, lower car of axle stands, put in about 4lts of oil, run car for about 10 mins, allow oil to settle, and check oil level on the dipstick, top up as required, do not overfil.
hope it helps
November 2010