When training your puppy to walk nicely with a loose leash, remember that you first need to spend time training your puppy to have value for being in the side position.
After your puppy will come to the side position, and hold that position for duration, then you are ready to start adding in motion.
(Side Position Video Demonstration)
When you add in motion, you add in ONE step. The instructor demonstrates taking one step, giving the cue “close”, and rewarding the puppy for following to the handler’s side and luring into a finished sit position at the handler’s side. (Four Video Demonstrations)
You will need to do the side-position ONE step “close” exercise for at least one hundred steps before progressing.