An excellent tip from the experts! Have you ever sewn a perfect buttonhole and then accidentally cut the stitches; or have you sewn a buttonhole in a delicate or knit fabric and have it sag or look frayed?
For perfect results, try placing a strip of fusible webbing between the fabric and your presser foot . After you have sewn the buttonhole, trim away as much of the fusible web as possible. Next hold a steam iron above the buttonhole and steam until the entire remaining fusible web is dissolved. This will help add stability to the buttonhole.