By what you said, I think you did right on that currently situation, because it's really hard to introduce someone to Bitcoin during a fast conversation. To do this more efficiently, you would need a calm conversation in a private place, with wide access to a desktop and a big screen. The important here is that you told BTC is an asset for the future, aiming long term holdings and profit, plus you explained about the risks of volatility, since price is constantly going up and down.

Now, if that person wants to know more about Bitcoin, you can guide him step by step daily.