Let’s think about why shaping the shoulder is important. A well-made sleeve cap is a thing of beauty in itself. And it boosts the appearance of the wearer. You are making the jacket, not buying it off the shelf. That means you can control how flattering the jacket is to you – or your client.A jacket sleeve should extend ½” from the shoulder tip, then fall straight down. This puts your shoulders in proper proportion to your neck, head and the rest of your body.Plus, it’s good camouflage! If you’re like me, your shoulders are sloped from spending hours at the sewing machine, then hours at the computer swapping e-mails about sewing. The right size and thickness in the shape squares up the shoulders and hides the roundness at the top of the arm.It also helps to hide if one shoulder is higher than the other. I call this the “books, bags and babies” syndrome. A shape can balance the height.If you practice yoga or lift weights, you still need a shape to support the sleeve cap and seam. You just need less.