The first thing I would do is this having been a finger shooter for the first 8 years of my 18year hunting life. Dont knock an arrow and just practice drawing and anchoring the bow with the release first. Keep your finger behind the trigger so as not to accidentally dry fire. Once you comfortable with anchoring then,

1. Get a good large target to shoot at
2. Stand around 5' from the target
3. Draw the bow, anchor and aim at your target
4. Once aimed, close your eyes and gently squeeze the trigger till it fires.

The element of surprise is what your after for accuracyof course you wont be accurate with your eyes closed but once you know how it feels and take several shots with your eyes closed then open them up and do the same thing you just did. The biggest thing is like they said you tend to want to punch the trigger and that produces poor accuracy, if you dont get into that habit to start with you wont have to conquer it later.
Then just shoot 20-30 arrows everyday and it will become second nature.
You shouldnt need an arm guard contrary to popular belief, If your elbow is in a locked position at full draw then your bows draw length is too long for you. You should be able to draw the bow to full and then just and only just unlock your elbow, this forces your forearm away from the string and the bow and gives you clearance and you wont be as wobbly out front with the bow.
Hope this helps
Steve