Whne you're in the stand all day, you've got to move. I avoid 'lateral' moves, such as moving my hand to my face to eat, as much as possible. For searching, simply rotating your head is nearly undetectable. With a face mask, I've even done this while deer were looking at me, and most of the time they don't spook.

Before making 'major' moves (sitting, standing, etc.) I just take a real good look around to make sure nothing (hopefully, because you won't always see them) is nearby.