LEAVE YOUR DOG ON A STAY COMMAND

You may begin to leave your dog on a stay command from either sitting, standing, or lying down. Sitting would be easiest.
The stay command is easier than it sounds. Proper timing will make this command simple. The secret is to use all of the cues we have available at the same time. We will teach your dog to automatically heel when you step forward with your left foot, and to automatically stay when you step forward with your right foot. Your right foot will be an additional signal to teach your dog to stay.

It must coincide with the voice command, and at the same time, you will drop the length of your lead directly in front of your dogs face as you move directly toward the end of your lead. If done correctly, we have four signals working in our favor. Dropping the length of your lead (but not the handle) will have a visual impact on keeping him in the stay command.

Give your stay hand signal, voice command, and movement of your right foot all together, as you bring your right arm forward and release the length of the lead from your palm. As you step forward with your left foot, place the handle of your lead into your left hand. If he should break the stay command before you have stepped forward with your left foot, use your left hand to collect the lead back into the palm of your right hand, and step back into the heel position, tell him "no", and repeat your sit command.

If this sounds contrary to the earlier discussion about correcting the last command that your dog broke, I AGREE.
BUT, to your dog, stay is a non-action! That means that he did not break the stay command, but rather, he broke the sit command. The position he was in was the stay command; the concept of stay does not mean much to your dog. If you leave his side correctly, and he breaks the command from the side, he must be corrected from the side.

Most of the time, you'll just step back as you say no, sit, stay, good, and repeat the stay signal and voice command as you step forward. Once you have taken two steps forward, even though he is behind you, if he breaks the stay command now, he has broken it from the front, even though he is still behind you. That means you'll need to place the handle of the lead into your left hand, turn to face him, collecting the length of your lead with your right hand, and placing it into the palm of your left, as the signal to sit comes with your right hand.

Try to get him sitting with as little physical contact as possible, drop the length of your lead, step all of the way back to the end of your lead, repeat your stay signal from the front, at the same time as you step forward on your right foot and continue directly towards him, collecting the length of your lead into your left palm. Now you may physically praise him, ask him to sit straight, adjust him, repeat the stay signal from the front as you drop the length of the lead and step back. Initially, we will give extra stay signals (with voice commands) at each point of our movement. We expect him to break the stay command when we move, so move smoothly, and distinctly, giving the signal with each new movement.

When correcting a broken stay command, do so without comment (except to say no, and repeat the sit command) or physical contact, if possible. Return to the point where he was when he broke the command, praise from that distance, repeat the stay command again as you quickly move in toward him, ask him to sit straight again, praise, pat, repeat the stay command and go back. Each point of movement requires handling of the lead properly to correct any mistakes quickly and without fussing. (By point of movement, I mean when you leave the side, when you reach the end of the lead and turn to face him, and when you begin to return to him). .