If someone says 'Make my day' the either mean it in a good or a bad way. Example: If a friend says to you, "let's go for a meal, that will make my day", this means you will bring joy to their day. If you say to an enemy "make my day", you would be prompting them to perform an action which would allow you to become victorious in some way, such as a fight.

This sentence comes from Clint Eastwood's "Dirty Harry" movies, most particularly the the movie "Sudden Impact", where the lead character says the line to a criminal he wants to shoot. It means that Harry was just anxious for the criminal to attempt to shoot a hostage he was holding, since it would give Harry the opportunity to shoot him, which would "make his day." An ex -American president, Ronald Reagan went on to immortalize the line in a speech about raising taxes. Generally, "make my day" is an Americanism meaning to have something happen to you that makes you happy.

complete your day