“Make a difference” is a vague goal, so you’ve hit upon the first part of achieving it – define what it is that you want to do with it.

You ask, “what is the one thing that I have, that others don’t have?” One thing that you have, and most people don’t have enough of, is appreciation of what makes them a unique, capable, and lovable person. If all you did is find one nice thing to say to someone every day – even a stranger, maybe especially a stranger – you could say that you made a difference by brightening each person’s day.

But maybe that’s not what you mean by this goal. So, what do you mean? Figure that out – that’s the first step.