Create a sense of immediacy and relevance in a lead sentence that will hook the reader, as if you are engaging him in a conversation or putting him into the middle of the problem that the paper will address.
Use the personal pronouns "you" and "your" to establish second person. For example, to open a paper on personal safety and ethics, you might begin with: "You are cruising a parking lot looking for a parking place, when you see two men struggling with a young woman in the back of a van. What should you do? It's hard to know what to do when your personal safety is at risk if you act, knowing that the woman's safety is in jeopardy if you don't."
Abandon second person and launch into third person, the traditional voice for essays, at the beginning of the second paragraph.
Show your lead sentence to your instructor to make sure that using a second-person hypothetical anecdote is acceptable if you are writing the essay as a class assignment. If this is a workplace assignment, check with your supervisor.