I work really hard on my timing for shot. When I am ready to take a shot, I

(1) make sure you are in a good shooting position (natural point of aim)
(2) breath in, breath out -- during that cycle I adjust my grip and remove the safety
(3) breath in, breath out a little, hold it, squeeze the trigger, breath out

When I shoot my Savage with the AccuTrigger, I depress the little trigger at the beginning of the 2nd breath out cycle and increase the pressure when I hold my breathing.

I do not like to breath when I shoot because my chest moves and that changes the sight. Also make sure you do not hold your breathing for too long or you will start shaking.

If for some reason I cannot take the shot when I am suppose to, I restart the process at (2). I assume you are still in a good shooting position. I never do:

breath in, breath out
breath in, breath out a little, hold it, don't squeeze the trigger, breath out
breath in, breath out a little, hold it, squeeze the trigger, breath out