The string vest was originally invented by Commandant Heinrik Brun of the Norwegian Navy. He used two pieces of herring fishnet made into an under garment. The strings trap air next to the body when another piece of clothing, such as a more closely woven shirt, is worn over it. Make your own string vest by sewing it from mesh cloth or by crocheting it. The goal is to create an open-weave item that can be worn under another.
Select a sleeveless vest that fits comfortably to use as a pattern. Place the vest on a large piece of newsprint paper and trace around it. Draw two patterns, one for the front and one for the back. The front will be similar to the back, but will need a lower scoop in front for the neckline. Add 1.2 cm (1/2 inch) at the sides, top of the shoulders and at the tail for a seam allowance.
Place the two pattern pieces on the mesh fabric and pin them in place. Cut around the pattern. Sew up the sides from the shirt tail to the underarms. Sew the tops of the straps together either stitching by hand or using a sewing machine.
Cut 5 cm (2 inch) strips of the jersey material, the width of the bolt. Pin the right side of the strips to the neck, the arm holes and the bottom of the vest. Stitch them in place, then trim off any excess material. Stitch the ends of the jersey binding strips together, fold them over, tuck under the raw edges to form a hem, and pin the fabric in place. Stitch down the edge of the binding.
Measure around the person who will be wearing the string vest at the hips and just under the armpits. Single chain until you reach a length that will go comfortably around the hips and around the chest. Slip stitch the end chain to the beginning chain. Single stitch a 5 cm (2 inch) band, working around and around the loop you have created; this will be the bottom of the shirt.
Single stitch in the beginning of the new row after the band is complete, then chain three, away from the band. Insert the hook in the second stitch of chain just completed, and single chain once, creating a corner. Chain two. Wrap the yarn around the hook once, then count over three stitches along the band from the base of the first chain. Insert the hook into the third stitch, then pull the thread back through the stitch and the loop on the hook; pick up another bight of thread, and pull it through the two loops on the hook completing a triple chain. Chain three, count over three stitches from the triple chain, make another triple chain. Continue this pattern until you have created a mesh tube that reaches to the arm pits.
Mark off an under arm space, a chest space and a back space using contrasting coloured yarn tied loosely onto the top chain; you will remove these markers later. Single chain from one arm marker across the front to the other arm marker. Mark the centre of the front. Single chain over to three stitches before the centre mark. Reverse, and single chain back to one stitch away from the arm mark, reverse and single chain over to within three stitches of the previous place where you ended on the previous row. Continue in this manner to shape a narrow strap that goes to the top of the shoulder. Leave the final loop loose, and work the opposite side of the front and the back in similar fashion.
Slip stitch the top of the straps together, and single stitch around the inside of the neck, and the inside edge of each armhole.