It's hard to tell someone what to do, each situation is different.
In general, if YOU make up your mind ahead of time what you are going to do, it's easier. None of that "read the goalie" stuff. Dictate to HIM what is going to happen! For example: if you are confident in a certain move, think to yourself that you are going to do that move no matter what. At the last second, you can always improvise a bit. For example, if you are good at the Yzerman/LaFontaine move, plan to use it. You can change the shot when you are done with the move, if the goalie has blocked your first option. For example, instead of tucking it home, you may have to go high glove-side. Or through the 5-hole, if he somehow cuts off the slide move. But too often you see players go down with NO IDEA in mind, and they fail every time. Make up your mind and do that move/shot.