Coming up with a room organization scheme can be a little stressful, because this is your opportunity to put your ideal workflow into action. Every sewing room has at least one sewing machine, natch, so first up is your sewing station. The number of machines you have plus the shape of your room may dictate how to set them up. U-shape is ideal, but if the room is long and narrow, a long straight line or an L-shape may be the best way to go.
Close by, you'll also need your cutting table and pressing area. Ideally, your cutting table should be a sizeable table at counter height that can accommodate the full width of fabric that you usually use, but your pressing station can be as simple as an ironing board.
Storage, storage and more storage will probably take up every extra bit of wall space. Drawers, cubbies, shelving -- whatever you need to put everything in its right place. And don't forget to leave space for an inspiration board, or even a design wall if you have room.
Don't skimp on lighting. Natural light is great if your room has a lot of windows, but you'll also need a good overhead lighting source and plenty of task lights at each work station. Last but not least, be sure to invest in a comfortable chair, since you'll hopefully be spending many hours a day in your new favorite room.