Youtube could be a good source find the many question's answer .You can get differnet easy idea from there and start to explain him/her .I think it will be better to show the price and the value of the recent time and also twhere it start from .He/she will get few idea that ho much it has value to the worls .Gradually start to explain him a lot option that how can he/she earn from here .I think that's how he/she can get the interest about btc and also on crypto market .Why not its make him/her to come on this platform explain him/her that how thousand of people are earning here and holding their asset become more rich .I think he/she will surely get it .