I start it and smoke out the neighbors, blast it with engine tuner give it 10-12 hours and run it on the old plugs in the harbor for 1/2 hour. I have already replaced the water separator/filter in the fall. I put the new plugs in after all the junk is blown out. Not a bad idea to bring fresh plugs out on the 1/2 hour voyage just in case the old ones foul up.
I suggest checking with a dealer for specifics procedures for your engine.