I've been trying push the puck ahead of me with R1 for 6 months now, resulting in me flipping the puck up in the air before sending it forward.

Now I find out you're supposed to tap Vision Controll - L2 (LT). This will improve my game so much!

Coming up from behind the goal, moving over to the far post side and a little away from goal, will give you a nice scoring chance (if you got the puck on the forehand side). To make it even harder for the goalie (I'm not in this example), pull the RS right (or left if you come in from the right side).
The hard part isn't really to score here, but to even get the chance. Most people know about this so they're gonna defend the slot like crazy. So you need to open up the slot with some passing. Playing the overload strategy - I find this play working from time to time:

Taking direct shots while moving is hard. So when you're going for a onetimer you'll be more successful if you time your passes so that the receiver is facing the puck when taking the shot. To do this you need to watch your team mates while evading opponents and time it all so you get an open passing lane just when your team mate gets into position.

What I really like about NHL 10 is that anything can happen. You think you've seen it all and then you take the lead after an insane goal like this one...