Encouragement, praise, reward..
Small treats as part of the daily food allowance used as positive reinforcement for good behaviour, which eventually can be replaced by verbal praise and patting/stroking.
Shouting at or telling a dog off(usually after the event) causes confusion and distrust, the dog may not remember what it has done, and the owner appears erratic and untrustworthy in the dogs eyes, which leads to fear and negative behaviours in the dog.