Pink Nike vinyl bag, how do you clean it?

O.k....peope you are a very helpful bunch. Here is my next problem. I loaned out the item described above and when it got returned it has some kind of stains on it. It's rust colored (ewww, I know) and if you have any expierence on how to get this kind of stuff clean, would you let me know? If I can get it cleaned I will NEVER, EVER let my little sister borrow anything EVER again. I will try just about anything and be forever grateful. (o.k...so I love this bag!!Lol) Thanks in advance for any help that you can provide! :)