In the main menu during the game, go to Coaching Options > Depth Chart, and you can switch people there.
Okay to formation sub, when you're choosing your play by formation you press R1 (for ps3, if you play xbox I'm assuming its RB) and then choose the position you want to sub in the graphic showing the formation at the bottom right.
yeah it sucks that they don't have the old formation subs you could set from your depth chart anymore. now you have to do it on a game by game basis.
