“Layout/Cutting/Marking: Let fabric relax overnight. Before cutting, compare the amount of fabric stretch with the amount required for the design. Generally the greatest stretch goes around the body.
Stitching: Start each new project with a new needle in the smallest recommended size. Change needles frequently; synthetic fibers dull needles faster than natural fibers. To check the needle for burrs, stitch through a nylon stocking scrap. Use polyester thread, which is more elastic than cotton. Wind the bobbin slowly. When wound on high, the thread heats up and stretches. Then, when sewn into the seam, it relaxes, and the seam shortens or puckers. For more elastic seams, stitch with a narrow zig-zag (W,.5-L,1), and stretch slightly when stitching. Or stitch on a serger with a safety-stitch and textured thread on the loopers.
Seams: Use stretch seams where appropriate. When sewing women’s swimwear, stabilize shoulder and waist seams and edges with stay tape or clear elastic.”