Someone gave you their password, their secret or their Saturday. What you do with that access is your whole reputation.

Access is always given on an assumption: that you will behave the same whether or not anyone checks. Every piece of trust handed over is a small experiment being run on you, usually without the other person framing it that way. Those results, added up, are what people mean by your character.

Treat borrowed access as if there were a record of everything you did with it. Return what you were given in the state you found it, and mention it when you used more than was offered. Nobody notices this until the once you get it wrong.