How to diaper a cat:
First you need a diaper with a hole for a tail
Approach sleeping cat with diaper.
Place diaper over offensive site
Quickly thread tail through open hole in center of diaper.
and fasten velcro around left hind leg to complete the procedure.
Take care to avoid scuffle with cat while bunny kick is in progress...
And try again, but...
know when to extract yourself from a bad situation and...
turn over all diapers to cat!