Potty training a puppy can be so frustrating at times that you might wonder why you got a puppy in the first place. You'll need to remember to employ plenty of patience as your puppy goes through the transitional phases and learns what is allowed and what isn't. Potty training slowly, in phases, is the easiest way to potty train a puppy.
Phase One
For phase one, you'll need to get a large, shallow box. A cardboard box lid, or even a box that looks a little like a kitty litter box would be ideal. Don't spend too much on it, as you're only going to use it for a week or two and then toss it. Grab some old newspapers and line the bottom of the box with them. Any time you notice your dog sniffing around, in preparation to go to the potty, place him in the box to do his business. If he doesn't seem to be interested in going in the box, you can purchase a scented spray that encourages it (see Resources). If he hasn't gone to the bathroom in two hours, place him in it even if he isn't showing cues. Soon he'll learn that the box is where he is to go potty. Place the box close to the door that you'll eventually use to let him outside.
Phase Two
Once your dog seems comfortable with going in the box any time he needs to use the potty, you can move onto phase two. In phase two, you'll move the box immediately outside of the door that you plan to use when he is fully potty trained to let him outside. Show the puppy where you've put the box, and leave the door open so that he can access it easily. Again, watch for cues that he needs to use the potty, and put him outside in the box any time he needs to go. Make sure that he realizes that his box is now outside, and he needs to go outside to use it.
Phase Three
In the final phase, you'll watch to recognize whether your puppy knows where his box is and uses it consistently outside. Now you can discard the box altogether and shut the door. Your puppy will be so used to going outside to use the potty, that you'll be able to let him outside of the closed door. He'll sniff around, looking for the box, but sooner or later he'll simply go potty outside on the grass or another designated spot. If your puppy seems to be having trouble going outside once the box is removed, you can spray an area of grass with the scent that encourages him to go.