My daughters had a cat themed 9th b-day party - for crafts we made origami cats that the guests colored with markers, then they decorated "baskets" for their cats (I had a bunch of plastic pint baskets from strawberries and they used scrap fabric and ribbon to decorate the baskets), and also cat memo holders - I made cat faces and bodies out of cereal box cardboard that the guests decorated, then we used a few glue dots to attach the head to the top of a wooden clothespin and the body to the bottom, then glue dot a magnet to the back - so it looks like the cat holds a memo in its mouth (pm me if you'd like to see a photo of how these turned out)
paper bag puppets are another fun and easy craft that can be easily cat-themed.
and if you'd like game ideas - you could play pin the collar on the cat, or do a bean bag toss - I drew a big cat face on a large cardboard box and cut out the mouth, and made easy bean bag 'fish' by tying some dried beans into a couple of mismatched kids socks and drawing fins and fish eyes on the socks with a sharpie marker.
