Even though most dog owners know what a release word is, rarely is it used properly or in sufficient amount.
While almost every dog trainer teaches how to use a release word I do not believe that its importance is stressed enough. What I usually see is an owner asking a dog to SIT, a treat is given, and then the dog gets up.
No matter the age of your dog or puppy the release word should be utilized immediately. The best way to teach the release word is to "catch" the behavior. This is done by using the chosen word while the dog/puppy is in the process of rising.
As your dog becomes accustomed to hearing the word before raising a slight voice correction might be necessary to tell the dog to wait until the release word is used. The most important thing to note is that the reward should come AFTER the release word once he/she knows the request (request being: SIT, DOWN, etc...).
Once your beloved fur child has a true grasp of the release word you can start to add more distractions. The more consistent you are with the use of the release word the more dependable your dog will become. Along with adding distractions, it is this time that you can add distance. This is the time when the word STAY can be used. When you use your release word don't be overly excited. If you are constantly excited when you release your dog he/she will anticipate the release instead of relaxing and staying patient. The less tense your dog is during the STAY the less likely he/she will be to break the STAY.