D.H.
I would make a mixture of some water with a little woolite and use a toothbrush (use the mixture sparingly) - and scrub, then wipe with a damp cloth as you go. You don't want it to soak up very much of the mixture, but at least it will help with the stains and germs. UV light also kills germs, so put it in the sunlight after you scrub. Hope that helps :-)