TEACH YOUR DOG TO SIT
The first thing you need to do is teach your dog to pay attention. He is paying attention when he looks you in the eye despite distractions. This is an exercise in itself, and for me, the foundation I build all others from.
I will start a new exercise with food reward, unless a dog is an idiot over food.
Usually though, you can find a food that a dog will work for, but not necessarily rip your hand off over. So find that balance.
Bend slightly over the dog, with the food just out of reach and slightly back of his head. He will want to see where it went. Most dogs just naturally sit out of the need to follow your hand. Repeat "sit" while doing this. When the dog does sit, say "good sit" in a nice tone and give him the food, still slightly over his head, don't make him reach forward and get out of position. Some dogs try to turn around to follow your hand, just keep positioning your body in front of him, while nicely telling him to sit. Eventually he will tire of turning.
Be calm. A lot of dogs need to do a lot of wrong things before they calm down enough to start to think. Don't chatter at him. Give the dog time to think this through. The one word "sit" coupled with no food until the dog does sit, may take time initially, especially in older dogs trained in stronger ways. They need to de-stress and realize there is no punishment in LEARNING. Puppies learn this way very quickly.
No Punishment while teaching !!!
Correction only comes for DISOBEDIENCE of a learned behavior.
Repeat this 3 or 4 times at a "sitting"(sorry,couldn't resist) and as you see the light bulb come on, start to give food less and less, and reward with a "good sit!".
Don't over praise and get him to break the sit. If he does, just re-do it, you need to find the level of verbal and patting praise that will work, and food.
Remember to ask for the sit when you have eye contact. Remember to use your release word when the exercise is over(make sure it ends on a happy note), DON"T over praise when you are done! Why should he work when all the praise is at the release???
Practice attention training when you feed, let him outside,inside etc.