I have two lists, one for home & one for my office. Each list gives a month-by-month--for all 12 months of the year--of things to be done that particular month.

Portable generators, for instance, need to be run UNDER LOAD about once each month (permanent/standby generators are normally set to cycle/test on/off each week or each month). This is obviously more crucial for businesses, but if you have a portable generator at home, either test it/run it monthly, or use it for other purposes, which accomplishes the same thing as "testing". They also need oil-level checks, oil/oil filter/air filter/spark plug changes. And unless you run it periodically, you NEED fuel stabilizer in the tank (emptying the tank isn't as good a practice as you are lead to believe).

At the office we give away unused food to food banks and/or social-/religious-service organizations each November, which helps them stock for the holidays. We use a water cooler at the office, but at home we cycle that water out in November (plants, wash cars, etc.).

I have plywood labelled for location, which end is up/out/etc., and I seal/coat it before I put it away. I just put batteries into normal household use, and buy new ones the following March or April.

Unused gas goes in cars/tools/lawnmowers.

It really is a year-round activity. Hurricanes are NOT the only calamity that can befall us, as recent ice storms, snow storms, freezes, tornadoes, floods, etc., bear out.