This is an timely thread. As Arne said, most of the better coaches will teach that aiming is to be done only once you are at anchor. According to Rod Jenkins, Arne and others, once at anchor you need to do a quick mental inventory of your bow/string hand grips, your anchor, and your alignment.....once satisfied that they're good, you can then "commit" to the rest of the shot sequence.
Many of us get so caught up in all of the physical elements of the shot sequence that the mental aspect of aiming gets passed over as our mind wants to do something physical. Once aiming.....accurate aiming, comes back into play, this can lead to target panic in one form or another for a lot of us.
Having been plagued by this since March, and having attempted to cure it with the help of Rod, Joel, and even a guy here in Texas who bills himself as a TP guru and produces a hypnosis tape to cure you, I decided that if aiming is the problem, aiming should be the cure. I have to get comfortable aiming again.
Beginning at 10 yards, I drew to anchor and did nothing but enjoy the aiming itself. Whatever happened with the rest of the shot sequence did not matter in my mind. Heck, if you can't aim without anxiety, good form doesn't matter. You can see where I'm going with this....bridge drills with the focus on simply getting comfortable at anchor and aiming. As the number of arrows shot this way increases, anxiety at aim decreases and our mind naturally returns to running the conclusion of the shot sequence in a proper manner.....which helps with the results of good aiming.
:D