I discover new artists mostly through these ways:
* Media: When the name of an artist repeatedly pops up (on tour announcements, on music sites, on social media accounts of artists I follow,...) then I usually go check them out at some point. I also trust some sites with their reviews and listen to well rated records.
* Last.fm: I submit every track I listen to to Last.fm since 10 years (Over 100k "scrobbles" at this point) and therefore their recommendations for me are really good by now.
* Friends telling me to listen to something. With some friends I also exchange a "Best of 20XX" Spotify playlist at the end of the year.
Interestingly enough, I attended a few hundred live shows in my lifetime and it only happened very rarely that I became a fan of an artist I didn't know in advance.