I don't think your dog is "ruined" -- just like most people, he hasn't had a perfect start in life. You can make this up to him, though it will take more time than if you had started out doing it correctly. Dogs are very forgiving and accepting of us poor, dumb humans!
Remember, he doesn't understand English, so your job is to teach him what words YOU associate with what actions. And then reward profusely when he gets it right or even makes an attempt in the right direction. Lots and lots of repetition, lots and lots of positive reinforcement -- praise, treats, play time, etc. I think of it as "lifestyle training" meaning that any time you are interacting with Zeus, you are training. Just be very conscious of the message you are wanting to send. Additionally, set aside some time each day to focus on specific behaviors, recall, sit, down, loose leash walking. Get into some classes with a good positive trainer. Hone your observation skills; learn to "read" his body language and remember that he already has your body language memorized. He's not reacting so much to what you are saying as he is to what your showing him with your facial expressions, movements, attitude. Read, read, read! You can do this! And you won't believe how this will improve your parenting skills as well! As with parentlng, even the best can learn and improve. Good luck and I'm so happy you've realized there is a better way. Behavioral studies have proven to you that we achieve more with a carrot than we do with a stick.
