Description of the Github flow: https://help.github.com/articles/configuring-two-factor-authentication-via-a-totp-mobile-app/
Description of the Google flow: https://www.authy.com/tutorials/enable-2-step-verification-gmail/
I'd like we invest time for that. Currently, we're asking users to setup 2FA, and they do stupid stuff like wipe their phone.
I've just tested the GitHub flow, I got three strong hints I need to backup the codes: 1. web / setup 2 factor 2. web / immediately after 3. mail. It also offers SMS alternative, but this part is perhaps less important than secure the scratch codes, and SMS can't be considered as highly trustable,