IMO, simple... take her to the section with the usa kids clubs take her to the mat let her swing... if she prefers lefty fine. I love that my son and I (he's been swinging a club and shooting a puck since 10months old, he'd stand swing hit the ball fall, stand swing hit the ball fall....repeat repeat keep going.) Let them love the game, then in a few years let them learn the game... she's 4, my sons 3 ... hell he already hits the ball like a man at 3 ! LOL... once he's ready, I'll get him to someone that knows wtf to do :) LOL
Good luck, just enjoy hitting balls with your daughter.. Jack and i play closest to the tree ring in my front yard everyday.. or we go to the field and let him swing away. It's fun :)
-P