Fill up a spray bottle half with hot water, half rubbing alcohol (70 or 91%}. Shake out the rug to remove loose dirt then lay down in bathtub. Get spray bottle and soak the rug. Squirt some dishsoap like dawn, antibacterial and anti grease, on the rug, then slowly fill up the tub until the rug is covered with the hottest possible water. Let that sit til the water is cool enough to touch then push down on the rug and agitate it back and forth while gently finger combing thru the fibers. Don’t bend it or pull it. The water will probably be dirty by now, so drain the tub, and then fill it back up with clean warm water. Agitate it gently then drain again. Repeat this, until the water is clean and soap free. Do a final rinse with cold water..a removable shower head helps with this process if you have it. Now gently roll up the rug and press on side of tub to get out extra water. Hang it over the side of the tub to air dry, or drape over something outside to dry in the sun. That’s how I cleaned mine 2 times so far with no damage. So hope that helps. :)

oh gosh! I am not sure! maybe ask Say Yes, the author of the post.

Thank you!