Four Stokes are alot easier, No need to use storage seal, Get some Fuel stabilzer put it the fuel tank (as per instruction) and run it for about ten minutes in fresh water.
Then if its long term storage.....
Take the plugs out and put a little oil in each cylinder, turn the flywheel over manually a few times to get the oil on the cylinders, then put the plugs back in.
Put a bit of anti corrosion stuff on the powerhead ( Corrosion Guard).
Change the Gear oil.
If the engine is coming off the boat make sure its kept upright to stop any water from going up the leg into the powerhead.