Muslin is a loosely woven cotton fabric, usually white, originally imported from the Middle East in the 17th Century. It became widely popular during the late 18th Century with the robe de la reine, Marie Antoinette's light new dress style. Today, muslin is the fabric used in the design industry to drape new styles. Muslin comes in a variety of weights, each used for different draping projects depending on the weight of the fabric that the final garment will be made of. Muslin does present some difficulty when working with it because as a loosely woven fabric, it tends to fray.
Mark your piece of muslin to be cut. You will need to make the line dark enough to be seen on the wrong side of the fabric.
Apply the tape on the underside of the marked cut line, on the wrong side of the fabric, with the tape centred on the line.
Cut the fabric on the marked line, cutting the tape in half. The tape stuck to the underside of the muslin will prevent the fabric from fraying.
Remove the tape after sewing and finishing the seam or just before sewing the hem.