When it is time to condition your puppy to the e-collar (generally 5-6 months of age), it's a great time to teach him a "Collar" command.

In preparation for training with the e-collar, you should have your puppy wear it every time he goes outside for about 2 weeks. You don't need to turn it on, but it should be approximately the correct tightness.

As you put on the e-collar, issue a "Collar" command. Make him hold still, which should be possible because he's still pretty young and small. Do the same thing when you come back inside and are removing the e-collar.

Soon he will figure out he's not going to be allowed outside until he gets his e-collar on, so he'll willingly come and stand still for you. This command can really come in handy in many situations where he's excited and it would normally be difficult to get him to hold still.