First of all get some silicone spray. Silicone spray can be found in the same section of the hardware store as WD-40. Before each use, spray the blades with the silicone spray. This lubricates and protect the blades. After each use, wipe the blades clean with a rag. Doing this easy five minute routine, will help you keep your mower in great shape.
To store for the winter, just spray the blades and wipe clean.
If you have a battery powered mower. Fully charge the batteries before storing for the winter. Depending on the battery, you may find it doesn’t have much juice after the winter. Fully deplete the battery and charge fully before using. To take care of your battery powered reel mower, do the same as the reel mower owners.