Vinyl can be cleaned with a little soap and water. When dry you can rub (very) small amounts of mink oil into it, and use a toothbrush on the sewn seams. Not much (just dab fingers to can), and only use your fingers, no rag. Bring it in to warm house and let it sit, and later it can be buffed with a shoe brush (it's not going to be shiny though). It keeps it soft and supple (as it can be).
Same with leather seats, and leather riding gear.
What you never use is Armor-All which is about looks, not preservation.
If you use too much, it will come off on your pants, later.
