I've said this for years, if it hurts, you're doing something wrong. It's really sad that people who are teaching two hand casting, don't put more emphasis on this. Usually, it comes from trying to over power the cast, a natural thing to do when things go to hell in a hand basket.
Too much body (back) english, too much upper arm, throwing the rod at the fish, etc.
Proper anchor placement & timing, getting in sync with your rod, technique, everything leading up to the final power stroke will yield amazing results with a lot less power than the other way around. If your anchor placement is not right, dump the cast. Start over, get the anchor right. And do not over power the cast & pull your anchor! A pulled anchor sacrifices power, and will probably cost you your fly as well.
Watch everyone, every style (more about that in a minute) listen to everything they say. At first it may amount to information overload, but some of it will stick. You can learn from everything, even from others mistakes.
Style: classic long line, Scandi, Skagit.They all look really cool, but before you plunge into any one style, realize they were each developed, by trial & error, to solve the problems encountered in their specific areas & the quarry in pursuit.
Once you have determined the style you think will be most successful in your area, concentrate your efforts in that direction. Start collecting DVDs, there are plenty to choose from. You Tube also has some amazing stuff. If you can, find someone to fish, learn from/with, compare notes.