Im not an expert, but this is what I do with no problems.
1. Run marine antifreeze through the flush kit till it comes out the back for at least a couple minutes.
2. Take plugs out and fill cylinders with fogging spray, crank motor over once or twice and put plugs back in.
3. Take battery out and put on a tender.
4. I spray down with wd40 too because I live on the shore and salt water is in the air.
I also like to top off the fuel tank and put stabilizer in it to prevent condensation from forming in the tank. Remember this is just what I do and I never had a problem. I'm sure others will cime in though.