Training a dog isn't something you do and are done with.
Training a dog lasts for as long as you keep it up and are consistent in the results you expect. It takes constant reinforcement and repetition. You train your dog to sit and every time you give the command and he does, you are training. What is most important is that you continue to reward your dog whether you use an "atta boy", a treat, or a pat.
Dogs are never "bad".
Love your dog.Respect him for what he is, not what you want him to be. Help him to be the best dog he can possibly be. Make a commitment to be there for him for the length of his life. If you have a dog for any other reason, you have it for the wrong reason.
There is no situation when hitting a dog is not avoidable. You cannot show love by hitting.
Your dog might do something that is unacceptable to you, but that doesn't make him bad. Animals aren't able to fully adapt to human ways of life. It is up to us to give them the tools and opportunities that teach them about our ways and in other instances it is up to us to adapt our ways to theirs. When your dog does that unacceptable thing, show her an alternate behavior. If she chews, give her something that she can chew on.
Of course it's yours, but your dog doesn't understand that. Dogs do not have an understanding of possession. If you're not using something your dog figures it's his to use until you explain to him what is out of bounds.
Our dogs want to succeed in pleasing us. Give yours plenty of chances to earn "atta boy" praise and pats for good behavior.
Our dog, Bailey, is an Airedale, one of the stubbornest breeds on this earth. He has taught me to choose my "battles" carefully. By that I mean, I have learned that sometimes his needs, his wants are more important than mine. I have learned to try to see things through his eyes, his ears, and of course his nose. What looks to me like him sniffing a tree is really him checking out the neighborhood: who has left their calling card.
I have learned that if I give him opportunities to succeed he will. If I give him opportunities to fail, he will do that as well. What he won't do is what I want him to do just because I said so.
When Fido Fails
The first thing to remember is that we all mess up some time.
When your dog does something you don't like, redirect his attention to something you do like. Let him succeed at that and reward him for his efforts. Rewards don't have to be treats. I have been amazed by how quickly "atta boy" resonates with our dog.
So your pup chews your shoe. Take it away from him and tell him no. That's done now. Move onto something he will like, something that he can succeed at. Throw a ball and praise him when he returns it. Reinforce a trick or behavior he has learned.
Our dog loves mozzarella string cheese and hot dogs. Both are easy to cut into bite sized treats. Train your dog with inexpensive, high-value treats such as these.
The bigger deal you make of something, the better your chances are of ingraining it into his memory. Attention is attention whether positive or negative. Learn to minimize the negatives and emphasize the positives and your puppy will as well.