Begin by marking the center 20 stitches on both sides. Then, in row 30 and row 31, bind off 13 sts, and then k18. Continue to row 32 and sew the sides together. Now, your sock should be round. Make sure that the heel is level with the rest of the foot.
The most popular method for knitting flat socks is to use 2 straight knitting needles and work flat. In the end, sew the seam. Many knitting patterns recommend using the Kitchener stitch, but you can also use other methods, such as crochet, to sew up flat knit socks. To give your socks an interesting appearance, try using contrasting yarn.
Once you have finished your sock, you can adjust the length, width, and/or heel by reducing or increasing the number of stitches in the front or back leg. To make a wider sock, cast on more stitches. For a narrow sock, cast fewer stitches.
This method of knitting is more complicated than circular knitting, and it requires you to use different kinds of stitches on both sides of the material. The right side is meant to face out, and the wrong side is meant to face inward. This allows for a more complex pattern and unique look than a circular stitch can produce.

200N GREEN WHITE RED STRIPES NORMAL FLAT KNIT SOCKS