Best way to potty train would be to use a crate that is they exact same size as the puppy. They only need to be able to stand and turn around while being confined. I would buy a crate that is sectioned so that you don't need to keep buying crates as the puppy grows. Most people say that for every month the puppy has been alive, they can hold their bladder for an hour...IE: 3 months - 3 hours. Personally I left my pup home starting at 5 hours and now she waits almost 9 hours until I get home from work. I usually take the pup out immediately after eating, then 30 minutes later as they say that it takes a half hour for a pup to need to poop. As far as when they are in the house, be ready to let them in and out as request as every half hour. Keep the pup busy with toys training and ice which helps with teething. Good luck.
Uma - Red & Black Female GSD
Lili - Red & Black Long Stock Female GSD
Molly - Tan & Black Female Yorkie Mix