Sewing Tip: When aligning seam edges in preparation for machine stitching, always pins perpendicular to the edge with the needle point facing inward.
Pinning perpendicular to the edge holds the layers more securely in place as well as provides a safer way to insert and remove the pins. Speaking of safety, in this position, the pin needles remains out of the way as you continue to handle the fabric layers in the stitching process.
Perhaps the most important aspect of inserting the pins perpendicular to the edge when sewing a seam is that this allows for easy, safe and comfortable removal during the machine stitching process. Pins are removed one by one as you approach them- you should never stitch directly through the pins. In horizontal alignment, pins are extremely fast to remove as they are being approached by the machine needle.