Heel and Heel-Sit.
To teach your dog heel, put your pup between you and a wall or fence, keeping the leash short. The wall will keep your pup in line. Add sit while walking along the wall. Doing this along the wall will keep your pup from swinging his butt around to face you before he sits.
Add Focus to the heel and heel-sit.
When walking along the wall and having your pup sit, then ask him to focus (or look or watch or whatever your word is).
Shown here are the 3 versions we used in class. All of them work the same. First, I had cones setup as a fake doorway. The goal is to have your pup sit on one side of the door, let you walk through, then release your pup to come through and sit on the other side of the door. In a public situation, this would allow you to close a door behind you without worrying about your pup taking off like a "bat outta hell". If your pup gets up before you have released him (as Heather did a few times here) then go back to the starting side of the door and start over. You may start by taking a step through, then coming back to him before releasing him through. You can use either stay or wait to tell your pup to stay on that side of the door. It's okay if at first he comes through and comes around in front of you, but the goal is for him to sit in heel position on both sides of the door. When entering a hallway or interior room, your pup may be hesitant. Also, I do not recommend practicing with an exterior door.
Doorways with a door.
When your pup understands the doorway without a door, begin using a doorway with a door. It can be a bedroom door to begin with or an exterior door. In either case, always practice with a leash. Have your pup sit in a place by the door so that he will not be in the path of the opening door. Give a treat, and tell him to wait. Turn the doorknob. If he continues to sit, praise him and give him a treat. Tell him to wait again and open the door a little wider. Each time he continues to sit and wait, praise and treat. If at any time he stands up, close the door and start over. Once the door is open all the way (both doors if you have two outside doors), then tell him to wait again, walk through the door, then release him to come through. Once he is on your side of the door, ask him to sit again, allowing you time to close the door behind you.
Game - Backup.
This is a fun game. To teach your pup to backup, stand in front of him and walk toward him. When he takes a step back, give him praise and treats. Increase the number of steps to reward him for. It may work better if you pick up your knees when you walk toward him. Your pup will likely be confused at first and may back up in a circle or off to the side, trying to figure out what to do. Simply get him back in front of you and try again.