(From Megan on Facebook) Hi! Thanks for writing! It can be pretty frustrating training a dog to not pull, but if you have the right training tools and patience, you'll be able to train him in no time! Do you have an Easy Walk Harness or a Gentle Leader halter yet? If you have an extreme puller I would get the gentle leader. It acts like a horse halter, because you'll have control of your dog's head and and it works like a charm on most dogs. However, some don't like having something strange on their nose and will try to scratch it off so be sure to attach a positive association. Make sure that you use lots of good treats when you put it on and when you walk him around with it for the first time.
You'll also want to get a leash that you can attach around your waist. Make sure it's short enough that he can't walk more than a couple feet ahead of you, but long enough that he can reach down to the ground to smell and check his pee-mail. With the leash around your waist you can stop every time your dog pulls and "be a tree". Wait till your dog calms down and takes the tension off the leash himself and then say, "Good! Ok!" and then take another step. If he pulls either stop and be a tree or turn and go the other way. Make sure that you're walking at a brisk pace because dogs walk along side you a lot better when they're in a "traveling" trotting mode. They are less interested in smelling and pulling you towards something when they're trotting along. It's good if the leash is around your waist because your dog will know the exact length in the leash that he has until it goes taunt. You can help him out a little bit, by making the interrupter kissy noise to get his attention when he starts to reach the end of the leash. You'll be able to get his attention and he'll have to lessen his step to look up at you. If he does drop back to you without ever putting tension on the leash in the first place, click and treat and tell him "Good heel!" every time he's traveling by your side. You want him to start realizing that a tight leash means that you stop and the fun stops. You'll know that he's getting it when he starts to automatically take the tension off himself because he wants to get from point A to point B as fast as possible and he's realized that a tight leash means he goes nowhere. He's probably learned like most dogs that pulling gets him where he wants to go and when he gets to smell the bush he wanted to smell or the other dog down the street. It's like getting a big reward and as a result the pulling behavior will increase and he's going to try pulling even harder next time, which is another reason that it's extremely important to be consistent in stopping every time he pulls. Just like slot machine gamblers, if he gets to win only once in awhile, it'll keep him hooked enough to keep trying.
You can also start teaching him what heel means by clicking and treating him for keeping his head right next to your side. When his head is by your side, click and then treat him right near the seam of your pants. Once he starts realizing that good things happen when his head is near the sweet spot, he'll start cruising right along beside you. When you first start to teach him this, take one step at a time and click and treat him each time.
Then take a couple of steps and click and treat him. Keep doing this until you are only reinforcing him for staying by your side every 50 steps or so and so on. If he's trying to turn sideways and face you, use a wall to keep him parallel to you as you walk, click and treat. If he pulls ahead when you do this, stop and be a tree and wait till he goes back to your side-- don't click and treat though, because he'll be thinking, "I'm going to pull, then stop, then get my treat." You have to be careful of chaining behaviors. Instead, just stop and wait for him to come back to you then tell him, "Good, Ok" and then take another step. If he keeps his head by your side, click and treat. If you are super consistent and patient, he'll be walking wonderfully by your side and he'll know exactly what heel means. And you'll be able to quit the game of tug o' war once and for all!