This is the completely wrong approach. I've brought up the money-earning aspect and I get flooded with "how much did you earn? can I have some money? How do you get it? How much will I earn per day, week, month, year? How do I know it's not a scam? How can people give away the money?" And an onslaught of other questions related to getting rich quick. Seriously, avoid yourself the trouble and keep the earning part out of it.
I agree that it is dangerous to sell the idea of Bitcoin to others as a means of trading investment, mostly because some of those people will then go on to buying some bitcoins without the slightest idea on how to store them, how volatile the price can be at times, as well as a whole slew of other considerations.
If you sell the idea of bitcoin on its merits, and then how they can use bitcoins to purchase things then they may be interested on a different level. I think that the best way to get somebody interested is to have them watch you carry out a transaction in a public place i.e. buying a coffee. That should fascinate them as it is unconventional and the transaction alone tells a story about what it is all about.