It's simple. There really is no maintenance, just occasional cleaning.

Ordinarily, the cleaning action of a rainfall will be adequate to wash your vinyl siding. However, vinyl siding and soffit should be washed periodically by hosing with a garden hose and clear water, particularly in those areas not exposed directly to rain. If you desire to do a more thorough cleaning, or where high soil collection conditions occur, use a soft-bristled, long-handled washing brush. It attaches to your garden hose and makes washing your siding easier.