Just tell them everything. Not only the positive side, but the both. The profits that you have gained also the loses you have made during your journey. Gains and loses are a part of the system. Ask them if they still have the courage to hold on even after learning all of that.
Choosing bitcoin as an option should be people's own choice. You can never force something to someone and wish for them to dedicate their self to it. If only they choose it on their own free will, you can teach them more what you know about it. Otherwise, there's no chance of teaching them.
Spread the knowledge, I will say. Nothing more you can do here. If they choose, they will come to learn more.