perpetration:

Perpetration: Something one has done or not done for which they feel bad or guilty—such as cheating, lying, stealing, getting another in trouble, badmouthing, plagiarizing, doing sloppy work, thwarting/sabotaging, communicating abusively, etc..

The way to complete a perpetration, to disappear the charge and any negative consequences, or possible aberrant behavior from the incident, is to communicate it verbally. *

For example: If you feel uncomfortable (if you are unable to be comfortable looking into a teacher's eyes) or if you are intimidated in the presence of a teacher, then you have an unacknowledged perpetration. The way to complete it is to say, or write,  "Dear Mr. Watanabe: I am writing to tell you I cheated on one of your tests."

* That is to say, you are already communicating it, nonverbally, with your uncomfortableness. Teachers can tell when they are in the presence of someone who needs to be acknowledged for something, most always it's a perpetration; possibly it's, "I feel badly for thwarting your success as a teacher by not applying myself, knowing I could con you."