I think jkat's advice is very good!
I would add that when a pup runs and hides to potty, it is usually because he has been reprimanded for pottying inappropriately. Instead of learning not to potty there, he has learned that it's not safe to potty in your presence.
Cherry asked about putting a pup in time-out for pottying on the rug. Most trainers say that if you catch them in the act, it's better to say no and whisk them off to finish in the appropriate spot - pee pad, outside, wherever. If he does finish there, "good puppy", treat. If you don't catch them in the act, there's nothing you can do. Pup won't understand why you're unhappy.
As for treats, continue them every time you catch pup pottying appropriately until he is 100% trained. Even then, occasionally treat - you want him to keep it up. As always,
behavior that is rewarded will increase in frequency. A food treat is much more rewarding to a dog than praise.
Good luck!