First, let’s clarify: there is a HUGE difference between teaching your dog not to pull on the leash, and teaching your dog to heel. A heel is an advanced behavior which requires your dog’s absolute focus for the entire duration of the cue. Loose leash walking is the relatively simple exercise of walking without pulling.
I’m not going to detail a heel exercise in my blog. Not now anyway. I will however be happy to outline loose leash walking. It is fairly simple: if your dog is pulling, stop walking. The reward inherent to your dog is forward movement and the ability to explore. If you move forward while he is pulling, you have rewarded him for pulling. He therefore understands that you must WANT him to pull.
The easiest and most humane way to retrain this is simply never to go in a direction your dog is pulling. Wait for him to create slack in the leash, to look back at you, at then move forward again. Precision in noticing your dog’s responses and a quick reward on yours will speed the process along, while rewarding an undesirable behavior will delay your progress. His reward is simple: allow him to enjoy the walk with you. A dog can walk on a loose leash of any suitable length. A small dog will need a longer leash to be able to easily create slack, where a very large dog might only need 2 or 3 feet. His positioning relative to you is unimportant in this exercise. He may walk behind, in front, to the left or right of you without remonstrance. His only task is to be sufficiently aware of your location and stride so as to not pull on the lead.
Conversely, you have a lot of work to do. It is important to be aware not only of your dog and his behavior, but also of your environment. Practicing obedience cues and short stays during your stops will help your dog engage his focus so that he remembers you’re there. It will also help him easily redirect should something in his environment become more interesting than you. If he is distracted and begins pulling, you can always change directions or redirect him with a cue he can focus on instead of the squirrel/car/dog that caused the initial distraction.
Start practicing this new behavior as you do with any other: no distractions. Practice in your home or yard to begin with, moving to more distracting and difficult environments as you improve. If you are frustrated with waiting for your dog to notice you, it is perfectly acceptable to change directions and move in any direction your dog is not pulling. Beware though, that this strategy, employed too often, can confuse your dog into thinking you want him to walk in circles, still pulling.
Have patience and persevere. Remember that if you need help, I’m always here. 🙂