Sew-on snaps make a great choice for holding two overlapping fabric edges together (such as a neckline gap on a shirt). Snaps come in a variety of sizes, in nickel or black metal, and clear nylon.
Try on the shirt and determine where to add the snap. Mark the spot with a safety pin.
A snap set is made of two parts: the ball half and the socket half.
1. Here’s how to sew on a snap. Thread a sewing needle with a 24"-long thread and knot the two ends together. Insert threaded needle into fabric next to the safety pin. Take a small "bite" of fabric and bring needle up, pulling thread through fabric.
TIP: Pull the thread all the way through the fabric with each stitch and you’ll prevent the thread from knotting and tangling.
2. Use your thumb to hold the ball half of snap over knot and thread on shirt front; bring the needle up through one of the holes (there are four) around the edge of the snap part. (Notice how the snap covers up the knot?) Sink needle into fabric next to snap edge and bring up through same hole to make a stitch. (The stitch loops around the outer edge of the snap hole.) Make three or four stitches through the same snap hole.
3. Travel from one hole to the next by slipping your needle through the fabric under the edge of snap, coming up in the next empty hole. Continue stitching the snap in place, making three or four stitches in each snap hole.
4. Slip needle under sewn-in-place snap and out opposite side; make a small stitch or tiny knot next to snap to secure thread and trim thread tail.
TIP: The ball half goes on the fabric edge with the buttons. What difference does it make? The ball part is kind of pointy. If it presses into your skin, it will hurt. When the ball half is sewn pointing away from the body, it won’t come in contact with your skin.
5. Mark the position on the shirt where the opposite snap half (the socket half) will be sewn.
TIP: Rub chalk on the ball. Overlap garment and press down on the ball so chalk marks the spot where you’ll sew the socket half.
6. Repeat steps 1–6 to sew socket half in place.