Personally, if I'm in a coffee shop or any store with some people, I pull out my wallet and subtly show them my Xapo debit card. Then they get curious on what kind of card is that since it doesnt look like the usual Mastercard or creditcard. Then I explain it from there on.
What's your way of spreading Bitcoin knowledge?

If I already earn much from Bitcoin and buy some properties or asset I will show to my friends and co workers that I earn those through bitcoin. I create new topics share my tips and strategies and what I learn about bitcoin. Not only in the form in other website and Social Media as well.