I have a SpotBot by Bissell that has a hose extension which allows me to clean furniture and mattresses. Then I put Borax on the spot to absorb any moisture, then vacuum that up. Most times mine hit the bottom edge of the bed though, not so much in the middle. Washable pee pads would be comfy for her to lay on...
Oh and I picked up a kitty diner that will elevate a small cat bowl about a half inch or so... might be better than using a towel...
Amazon.com: Hagen Catit Stainless Steel Double...
or
Walmart.com: Hartz Living Stainless Steel Pet Feeding Dish: Cats