I was lucky when my pup was little because almost every time I answered the door --if my he got through - he would turn around and followed anyone back into the house.     
BUT - occasionally instead of turning around and coming back, he went bouncing off --following my other dog.  No good - right!    
So - I taught him to stay back about 10 feet (sitting) before I answer the door.   He learned this very quickly and is very good about it.     
Before I answered the door, I turned around and walked toward him (with myself between him and the door) and moved him back (with my feet) to where I wanted him to be.  I told him to "sit" and then "stay" --- I kept my  
eye on him as I went back toward the door with my hand in the "stay position" and myself reminding him to stay as often as I needed to.    
At first - if he started toward me - before I answered the door - I'd repeat the above.  And, after only once or twice - he learned to sit back and stay when I answer the door.     
****** Got to let you know - my dog is not a rocket scientist.  The only tricks he knows are "sit" and "stay" --- but these are the lifesaving ones - and should be the first ones we teach.     
Be sure you teach your new little puppies these two commands.  Start as soon as you get your puppy - 8 or 9 weeks old is not too early.     
Use the hand gesture - and a simple one- word command.   I'm sure you'll find that these two commands take almost no training.  The dogs do this almost automatically.  (I really felt like I didn't even train my little dog to do this - he almost just did it on his own.)     
What we need to practice with them: 
   1)  Teaching them to stay for longer periods of time - and 
   2)  Teaching them to stay - even if they get excited and really want to  
        bolt     
*** Easiest thing I ever taught my dog.....     
Carol Jean        |