I contracted a temporary worker for two weeks, to cover vacations of another person. There is no contract, only a word agreement. His work is to cover a turn during the night, checking some systems during his turn. The problem is that in his first week, this worker did some things that deserve a sack. He left the working place for several hours, he allowed two of his friends (two girls, I don't have details) to enter to the office and, finally, he had an argument with these friends, that demanded the intervention of the guards of the building.
The point is, since I have to sack him, how can I communicate him that I have to sack him? While explaining him that he made several mistakes, in order to make him peacefully accept his fate?