Sewing and altering a muslin test garment is time-consuming but essential to developing a beautifully fitted couture garment. It enables you to assess fit and design proportions and try out unfamiliar techniques without risk of damaging expensive fabric. It also prevents you from overhandling your fashion fabric. Once your muslin is correctly adjusted, it becomes an invaluable source of information that will last for years. Couturier Susan Khalje shows how a detailed approach to muslin makes for exquisite garments in this article from Threads #151.