Come

Training you dog to come when he is called is time consuming but simple. As with most training - food and praise is the most effective method of training.
Make sure the dog knows that you have food, allow him to play on his own - call his name with the command COME.
    If he runs to you, sits at your feet, and allows you to grab his collar - reward him with a treat.
    If the dog does not complete these tasks when called - show him the treat - then put it back in your pocket, let him know what he almost had.

When the dog does what is desired, he is rewarded with what he wants most: food, praise, and or attention.
A neat little bit of info that was passed to me in training: to complete the COME command wait until the dog sits in front of you then grab his collar. This will get him in the routine, because most times when you call him you need to get control of him for some reason.