After a lot of puppies, I've FINALLY figured this one out. My 5 month old puppy isn't perfect yet, but we're so much further along at a much earlier stage than any of my other dogs. And he seems to be having a lot more fun on walks.
Start here: https://www.germanshepherds.com/forum...ge=1#Post35064
Teach your puppy FOCUS first. Get a rock solid focus. Do all of your regular training (sit, down, wait, etc), and work on focus. When you give your puppy her meal, don't just ask for a sit/wait, but hang out until she looks at you (at first it's going to be a split second glance, that's ok).
I sit and have my pup facing me and just wait for him to look at me, then I click and treat. He loves it. It's easy money for him.
A clicker makes learning focus go even faster because it captures that nanosecond that your pup glances at you at first. But if you can't manage clicker and treats and puppy, just work very hard on getting your marker word (YES!) out as fast as possible.
Be very generous with treats. Once she has a good focus at home, take your puppy out a lot, to distracting places and work on focus. Just plop her down so she's facing you and keep doing the exercise just like you were at home.
Once you have that....once your puppy knows that "looking at my owner means good things happen"... (which is probably at least a month or two away), THEN you clip a leash to her collar. Stand in your living room in front of her and tell her "focus" and continue to do as you did before. Then put her in the heel position (this is new!) and do the same. Take a step and do the same. Then two. After about a week of this, move into your yard, and do the same. Don't walk around: just let her experience being outside, in the heel position, looking at you and focusing.
The next day, start walking around your house continuing the focus lesson. Then the yard. Keep using treats. Be sure you're treating from your LEFT hand if you're having your dog walk on your left side. (Hold the leash in your right hand). Otherwise, you will inadvertently turn toward her slightly, which will make her turn and move out of position.
Don't go too fast. Any time she seems to struggle, slow down, or if necessary, back up. While you're doing the walk around the house and yard, continue to take her into distracting public locations and doing the sitting focus lessons.
Within a few weeks after starting the WALKING "focus" training (about 3 months from now), you should have a dog that will be able to walk along next to you in a heel position, glancing up at you regularly. You need to be sure that you put her in a proper heel position when you start so that she's not swinging her head backward to look at you, which can cause neck problems. By learning to glance at you, she will learn to keep pace with you and "check in." Because you've been training her to focus in distracting locations, she will be far less likely to fall out of position if a distraction is present. And if one is, you tell her to focus, and she should automatically tune back into you.
Don't be in a rush to phase out treats (I plan to carry treats all of my dogs' lives. It's just easier to assume that, then worry about when I should be fading them out). Heeling is one of the hardest things to train a dog. But a dog that knows how to heel is a dog that is easier to train in most other areas of life. If you can imagine having a relationship with someone who pulls you along the street whenever you hold hands, you can see that the relationship isn't really very balanced, is it? If your dog heels automatically and focuses on you, she won't be lunging after other dogs, trying to pick up weird things on the sidewalk, etc. So training "leave it" and such things becomes much easier.
In the interim, of course you should continue to walk your dog. Use a Sensation or similar harness so that she doesn't learn to pull on a collar.