To check eye dominance ...touch your thumb and trigger finger of each hand together to form a circle..fully extend your arms...with both eyes open..focus on some object that will fit inside the circle...close both eyes...WITHOUT moving your arms...open one eye.see where the object is in the circle..close your eyes, then open the other eye...one eye will have the object perfectly centered...the other eye will have the object moved to the side...the perfect centered side is your master eye..