Lie face down on an incline bench with a light dumbbell in each hand, arms hanging straight below your shoulders. You'll move through three positions in a row: arms angled overhead to form a Y, then straight out to your sides for a T, then bent so your elbows pull back like you're squeezing something between your shoulder blades for a W. Raise each shape only as high as your shoulder blades can pull without your arms taking over, pause briefly at the top of each, then lower before moving to the next letter. Light weight is the point here; this targets the small stabilizers around your shoulder blade, not something you load heavy.