There really isn't much to summerize. The engine and drive 'summarize' themselves when it is started. I prefer to do this on a hose and muffs rather than at launch time. Anti-Fouling paint, wash wax. The A/C either gets primed or is flooded with propylene glycol so the first time it runs it too is summerized. Fill the fresh water and pump out any propylene glycol from the water system. Repeat to flush clean.
Open the seacock to the head and start flushing. This gets summerized the during its first use after launch like the AC.
summerizing is about cleaning, washing, waxing, painting and fixing broken stuff and preventive maintenance, and zinc's.