I know it's ironic, but one of the first commands you'll need to teach your dog is the one that means, “Take a break!”  This is called the release command.  It is a crucial tool for all types of training.  Not only is it important for your dog to have a few seconds (or minutes) for a break, but the release command is often the only proper way to move your dog from one exercise to another.  

Choose a word for the release that you can consistently say in an upbeat, happy voice.  You'll want the sound of you saying this word to be great news to your dog.  Many people choose the word, “OK!”  This is a fine choice, but if you choose this word, you must be careful not to use it while training your dog.  If you are having a battle of the wills with your dog while trying to make it sit, and you sigh and say, “OK, let's try this again,” and your dog pops up and jumps around with glee, you can't blame your dog.  For this reason, some people try to think of a happy word that won't accidentally pop up in the course of normal conversation:  popcorn, ice cream, ka-pow ... you get the idea.

Teach your dog the release command by alternating it with the sit command (which we'll discuss soon).  Tell your dog to sit.  Praise your dog.  Then give the release command.  Then begin again.  You can teach the dog to love the release command by acting very excited when you give it.  Say “Popcorn!” and then dance around like you're having the time of your life, and usually, your dog will too.  Give your dog frequent breaks while training.  It will thank you for it!