Wash and iron the fabric before you begin to allow for shrinkage. If you’re making a reversible sling, lay the two pieces of fabric on top of one another and align the edges.
Measure for the length of your sling by using a flexible measuring tape. Begin at one shoulder and measure across to the opposite hip bone and add 3 inches. The additional length allows room for the pouch to will hold the baby.
Cut down the center of a standard 44-inch wide bolf of fabric so you have two 22-inch lengths of fabric. This will allow you to make two slings from one yard of fabric. You will cut these to your specific sling length (measurement from shoulder to hip) in Step 5.
Fold the fabric in half lengthwise and then in half widthwise. Be sure to line up the cut ends of the fabric. It should resemble a long rectangle.
Lay your flexible measuring tape across the bottom of the folded rectangle and place a pin where your personal measurement is in the lower right corner. Make sure the pin goes through all the fabric to keep it in place. Do the same thing on the top of the fabric and place another pin at your personal measurement.
Measure 3 inches back from your personal measurement on the top of the fabric and place a pin. Move down ½ inch from that pin and place another pin. You will use these pins as guides to create a curve from the bottom pin to the top lower pin. This will create the peanut shell part of the sling's design.
Cut the fabric, starting from the bottom, following the curve up and stop at the lower top pin. From the lower top pin, cut straight up to the top of the fabric edge for your seam allowance.
Unfold the fabric, ensuring the layers remain lined up if you’re making a reversible sling. Place the long, straight edge of the sling in the sewing machine and stitch the length about ½ inch from the edge. Be sure not to sew the curved edge.
Remove the fabric from the sewing machine and turn it inside out. Iron the seams and then fold the fabric in half, ensuring the two curved edges are lined up. Check to ensure the corners are also lined up neatly.
Place the fabric in the sewing machine and stitch the curved edge with a 3/8-inch seam allowance. Remove the fabric from the sewing machine and trim the excess close to the seam.
Turn the sling inside out again so the raw edge of the seam is inside. Using your iron, press the seam in place.
Place the fabric back in the sewing machine and stitch along the curve 5/8 inch from the edge. This new seam will hide the raw edge remaining from the first seam.
Remove the fabric from the sewing machine and iron the final seam so it lays flat. This will help when you get ready to sew the curve of the pouch, which will want to pucker up and bunch on you.
Put the fabric back in the machine and sew along the right edge of the seam. Sew slowly to resist any puckering as you sew around the curve up the pouch. Trim excess thread and add any details, like patches or monogramming.