I really suck at aiming myself. The thing I do wrong is that I allways move the LS 100% in the direction I want to shoot. This is because most online games are intense with very little time to take shots, so in an effort to take a quick shot I move both the LS and RS too fast and too hard. The trick to aiming is to aim soft. Aiming is sensitive. If you aim the left stick all the way left, your will miss the goal a lot of times (especially one-timers) unless you're controlling a player like Ovechkin. So if "all the way left" is 100%, then go about 75-80% left to get a shot that will stay inside the goal. Also note that when moving the RS to take a shot, moving it as fast as you can won't make for a harder shot or anything, but may affect your aim if you're not inside the "shoot margin" - 11-13 o'clock.

Also, on onetimers, you will hit the net a lot more if you wait with moving the RS until you've received the pass. I tend to move the RS right after sending the pass away with the result that I miss the puck all together from time to time.
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