Buttonholes may seem like a difficult undertaking for the beginning sewer, but they are surprisingly easy to make now that the majority of sewing machines are capable of automatically sewing a perfectly-sized buttonhole by using a special presser foot. However, the buttonhole foot can only be used to create buttonholes up to a certain length. When a garment requires one or more extra large buttonholes, it can be done with your machine's traditional presser foot by following these steps.
Determine the length of the buttonhole by measuring the diameter of the button, then adding the height of the button plus 1/8 inch. If you're using a particularly heavy fabric, you may want to add an additional 1/8 inch in length so it will be easier to button and unbutton the garment.
Mark the position of the buttonhole on your garment using tailor's chalk. Draw a straight line equal to the length of the buttonhole, then add a short perpendicular line at each end. The long line will represent the centre of the buttonhole that will be cut open once you're finished stitching, and the lines at each end represent the bar tacks, or the wider stitches at either end of the buttonhole.
Set your sewing machine to the zigzag stitch setting. Adjust the stitch length to 0 or 1 and the stitch width to 5. Place your garment on the machine and lower the presser foot, then slowly lower the needle to the upper right corner of the marked buttonhole. Create your first bar tack by sewing several stitches forward and several in reverse to lock the thread and prevent your buttonhole from unravelling. When the bar tack is finished, turn the machine's hand wheel if necessary to move your needle to the rightmost position.
Change the stitch width to 2 and sew the length of the buttonhole, keeping the stitches to the right of the line you've drawn. When you reach the end, ensure that the needle is again in the rightmost position, then set the stitch width back to 5 and sew another bar tack. When this bar tack is finished, lower the needle into the fabric at the leftmost position.
Lift the presser foot and rotate the fabric 180 degrees, using the needle as the axis, so that the needle is now on the right side of the buttonhole. Set the stitch width to 0 and move the needle to the rightmost position by sewing one stitch. Change the stitch width back to 2 and again sew the length of the buttonhole, keeping to the right of the chalk line. When you reach the first bar tack, sew a few stitches in reverse to lock the seam. Remove the garment from the machine and trim the ends of the thread.
Place a straight pin through the bar tacks at each end of the buttonhole to safeguard them against being accidentally cut open. Starting at the bottom bar tack, poke the longer end of your seam ripper through the centre of the buttonhole and carefully slide it toward the top bar tack, thus creating the open space for the button to go through.
Use a piece of scrap fabric to make some test buttonholes before sewing them on the actual garment. If possible, the scrap should be the same fabric you're using to make the garment. Buttons are traditionally located on the right side of the bodice for women's garments and the left side for men's.