Long running stitches are basting stitches; nothing fancy here. These stitches should go in fast and they should be able to be removed quickly because they are temporary. They help hold the fabric while you put in the permanent stitches. Unlike pins, the stitches do not distort the fabric and they won’t prick your skin. The size of the stitch is also relative to the size of the piece you are working on. Notice the stitches on the heart are larger than the stitches on the hexagons
You can baste by hand or by machine. I used my machine to stitch on the left side of the heart. I used the longest stitch length and did not knot (reverse) at the start and finish. These stitches go in faster but are more difficult to remove than hand stitching. On the right, I hand stitched. Once again, I did not knot the ends because it easier to pull out the stitches.
BEWARE! Try to use white thread for basting. Some colored thread will bleed into the fabric; especially if those basting stitches stay put for a while. I used dark thread because it photographs well and the stitches were only in for a short time.