Now that you have determined what you dog knows, you have created a training plan for the things he didn’t know, and you can start to use those things to give your dog information when he needs it.
Find one area where you are telling your dog “No.” First, “No” does not give your dog any information on what TO DO. Pick one of those behaviors that your dog knows really well and ask them to do that instead!
How did it go?
“It went well!”
Congratulations, you are now a dog trainer. Contact me if you would like a job! 
“It wasn’t perfect but I can see how this could work.”
That’s great! That means you chose the correct behavior for your dog. We just need some more practice to teach the alternate behavior. Stick with it and be consistent! Great job!
“That was a disaster, what are you talking about!”
HAHA this is what I expected! If your dog has been practicing a behavior for awhile, then it is going to take some time to re-learn the new expectation. Start small, just like when they learned the behavior in the first place.
Let’s take begging for food as your chosen “No” behavior. Most people tell their dog “No” as they are sitting down to dinner with the family. From your dog’s perspective, he is getting no attention and no delicious food. Of course he is going to stare at you while creating a puddle of drool on the carpet.
What behavior could you ask your dog to instead? My dogs go to their mats and lay down. I made sure that was a very well known behavior before asking while I am eating dinner. The first few times I asked, I had the mat very close by so I could get my dog and put them back on the mat if they wandered off. After a few minutes of that, they went into their crate if they were not staying on the mat. Over time they left their mat less and less, and eventually I forgot about them while I was enjoying dinner with my family.
Moral of the story
Make a decision and stick with it! Most dogs, like children, benefit from rules and structure. If they know what is expected of them, they will default to those rules and behaviors more and more often.