Just as you have to housebreak your dog and teach him all sorts of other expected behaviors, you'll also have to train your dog to accept wearing a knitted sweater.
If you do not plan to let your dog roam free in the house while you are not at home, crate training is another way to housebreak your pet.
He can be difficult to housebreak because of his tendency to become distracted.
It's called How to Housebreak Your Dog in 7 Days from Shirlee Kalstone.
The faster you housebreak your puppy, the easier life will be.