How to potty train a puppy.
Most dogs by nature are quite clean and will never soil in their perceived area unless given no other choice. The trick is for both you and your puppy to get on the same page as to what their perceived area is. If given too much area, such as run of the whole house, the dog by nature will make its own boundaries within that house and go potty where it feels it is not significant to bother him.
I recommend restricting a new puppy's boundaries whenever it cannot be 100% supervised or tended to. This is easily accomplished by using a crate. Put them outside first briefly and then in their restricted boundary, until you again can supervise and play with them. Whenever you put them in the crate and take them out, you should let them try to go potty. When they do go potty outside, praise and a special flavored treat are a good thing and the puppy quickly associated this with going potty and special attention. If they do not go potty outside, they should go back into their restricted boundary and not taken out to be played with for a few moments, then try again outside for another potty trip.
Also, the outside potty area should be restricted. It should not be a big play area, but a potty area. If too big, the puppy will play and forget to go potty and when brought back into the house go there. The puppy should only be in the potty area a short time and not left. If they do not make use of the potty time, they should go back in the crate without praise or a treat. Soon they will learn to get things done quickly and then on to treat and playtime.
As the puppy matures and becomes more used to the routine, the boundaries can be increased and finally eliminated. Hope this helps,