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How to Toilet train your cat!- No more messy litter boxes!  
Toilet Training your cat is simple, but takes a while...
Get a bowl of some sort that fits perfectly into the toliet. Fill it with litter, and make sure your cat knows that the litter is in there. Help get your cat used to balancing on the edge of the toliet seat by sitting him up there, with his bottom facing into the toilet. For the next few days or weeks, help him get used to that process, getting up on the toliet seat and helping them understand that the litter is IN the toliet in the bowl. After a few weeks or so, or at least once your cat just naturally gets up there and goes in the toliet litter bowl, TAKE THE BOWL AWAY. Now, you might be thinking, what if they fall in now that the bowl is gone? Well, after all the time that he has gotten used to standing on the edge of the toliet seat, that should be no problem. Even so, be sure to err.. supervise every time your cat uses the toliet. If he actually does GO in the toliet, reward him with a treat. The whole process should take about 1 or 2 mounths. Like I said, be patient!