Dear Cat Owner,
How to bath your cat!
1.  Thoroughly clean toilet
2.  Lift both lids and add shampoo
3.  Find and soothe cat as you carry him to the bathroom.
4.  In one swift move, place cat in toilet, close both lids and stand on top so cat cannot escape.
5.  The cat will self-agitate and produce ample suds. (ignore ruckus from inside toilet, cat is enjoying this.)
6.  Flush toilet three or four times.  This provides power rinse, which is quite effective.
7.  Have someone open outside door, stand as far away from toilet as possible and quickly lift both lids.
8.  Clean cat will rocket out of toilet and outdoors, where he will air dry.
Sincerely,  The Dog