One problem with kitty litter is that you need to throw it away, usually using plastic bag. In case you want to save plastic bags, consider using flushable litter.
With flushable litter made from non-clay materials, you can toss everything in the toilet and get rid of it without the hassle of bagging everything up. Of course, it would be easier if you could just teach your cat to use the toilet directly, but since cats always make life harder for everyone, that’s probably not an option for most people since your cat will just crap on the floor in protest.