The litter box is the key answer. You do have one, correct? When I was a first time host of a cat, I'd forgotten that part... LOL.. the bathtub was the next best thing for it. . . "In the house" is a given if you intend to keep it as a house cat. Cats are actually very clean animals... and tidy. They know where they need to go and what they want. Focus on getting him/her to the litter box when it's time to go and no other. I keep our litterbox that's always available in a bathroom... don't shut and lock the door! The cat's gotta have a place to go too!!.. even while you're away. Don't lock the cat out of where it's gotta go!. . After that, if training is an issue, (I've done this since I've moved a few times with the same cat), I'll close the room off where the litterbox is and leave him in there for 12 hrs or so... so he could figure out where the litter box is.. . Keep the litter box clean, though. Cats would probably do a better job than we would. Sift through it with one of those scoopers to pick out the poop and replenish what's been taken out with new litter. Once or twice a week is my routine.. . . I hope it helps,. Chris