One thing you can try is to do drills/games which she will only succeed on if she does things in a correct way. For example with my DD, her swing is often too flat. Things like having her hit off of a low tee and giving her the cue to hit it up into the net or throwing her low pitches in front toss and having her try to hit it over the L-screen promote a better barrel path without any excessive instruction. She will have to self-organize her body to try and do what is being asked. Another one is doing self-toss for max distance which can be useful for getting better separation/sequencing in your swing for example. Stuff like that.