This is a helpful video to show how to clean some stains, mildew, weather wear, etc on seats. You can also apply the same technique to other surfaces on furniture or inside your home.

The basic tools are a degreaser, which I use "Awesome", a drill with a brush head, and some water. The product "Awesome" can be bought at local Dollar General or Dollar Tree stores or online as well. I recommend using it on a small area first to see how it interacts with the surface. This videos is of vinyl seats from a Ford F250 truck and this process has been done previously so its been acceptable to work on this surface. The degreaser can also be watered down to make a less powerful solution.

I hope this helps someone.

Enjoy!