My wife and I adopted a 2 month old Australian Shepard/Irish Setter mix (supposedly) from a shelter a week and a half ago. He's a really energetic puppy and seems to learn fast. We've already taught him how to ring a bell to go outside to play or pee/poop with minimal accidents. And he really does well in his kennel.
The one big problem we're having with him is his biting. I understand he's teething and wants to chew on things, but he really likes chewing on my wife and I. Like almost excessively. We've tried substituting toys when he bites us after a firm "No". That works for a very short time, sometimes a few seconds to a few minutes before he's back trying to chew on us. He'll chew on any part of us: hands and arms when we're petting him on the back; legs, ankles, and feet if we're walking or sitting. We've even been trying to yell "Ouch" in a higher pitch to try to get him to pull back, but it just makes him want to play harder and bark. Same with a firm "No" sometimes, even though he knows the meaning usually for other things. I've tried to ignore him as well when he bites, but again it sometimes makes him try to play harder to get my attention back. And if I walk off, he'll just go after my ankles or feet.
Anyone have any suggestions? Also anyone have decent training videos or guides for other things? There's tons out there, but I know some aren't "good" methods of training.