lock (traps,stance,hook,bow arm), relax all (but traps/stance), then lock(eyes on your spot).
lock your hook, relax your hand.
hold your arm strait inline,semi locked but relaxed.
And for me with heavier draw bows, to stabilize,the deltoids up and rotator cuff muscle, and rear delts on most are weak as hell.
So to counter it, even if you dont work out is to flex your trapezius muscle.
It runs all the way down to middle of your back.
When flexed it will help hold your rear delts stable.
Try it, flex your traps and relax everything else,
try to touch your shoulder blades together while all else is relaxed
And see how much easier it is to hold your arm up with weight against it.