Gigs. Either just buying tickets to random local venues. Our go see your favourite artists live, but make sure you get there early enough to see the openers.
I've discovered so many amazing bands because they opened for bands I already knew I liked.
If you can't physically get to gigs then you can even just look up who your favourite artists are touring with, that will give you a pretty good sense of them being similar.
It's great! You're also supporting the local scene which is massively important.