I just usually show my portfolio and the price when converted in currency. That is enough to get my friends to notice and inquire about BTC. First thing needed to teach others is their will to learn. Once their hooked, they absorb every detail more efficiently. And then they tell their spouses, friends, etc...
Yeah this is good but I think the best way could be the internet advertizing like if bitcoin will be spread all over the world through internet and television chennals then bitcoin will become the best currency of the year, now showing your bitcoin capital can be dangerous for you security so it is good to just advertize bitcoin and tell everyone about bitcoin so they will also be able to know it and they will take part in bitcoin.