Indeed, one should not invest in anyone's recommendation or wisdom. Must first have proper understanding, education and reasoning power about Bitcoin and Cryptocurrency. If not, it can cause a lot of damage.
Just educate first the people that you're talking to if they're interested to know more about bitcoin. Tell them the good things about bitcoin but don't forget to include the risks that someone will take if they ever decide to invest in bitcoin.
Avoid giving guarantees because that's where you're just making yourself in trouble because the person you're talking to might blame you later on if results didn't go according to what you've guaranteed.