Your teaching and the words you pick to describe what Bitcoin is to someone will determine how they will react towards you if investment goes wrong or right, you can start by telling them how price of bitcoin can fluctuate and can’t be predicted they can’t get quick profit from it like they are assuming or see online, you give them the vital information and allow them to decide so that they can take sole responsibility for their decisions and not go hold you accountable for their lose or impatient.
Yes, the first thing that needs to be conveyed when we tell people about Bitcoin is our opinion so that it is easy to understand, and by explaining it simply, maybe they will easily accept it and they won't ask many questions, I think that's enough to convince them so they won't talk too much or pressure us.