a pillow using fancy 3 cord binding around the edge.
Do you have the binding/piping ready-made already, or are you wanting to sew it from scratch using bias cut binding and cording?
Here are instructions and video showing how to sew a basic piping, then attach it to a cushion cover. You will need a zipper presser foot for your sewing machine.
The link below shows instructions on how to make double cord piping, also called double cord welting.
You will need a double piping/welting presser foot for your sewing machine.
Cut the fabric to suit leaving seam allowance. Sew cord to right side of one piece of the fabric facing inwards along the seam line. Then sew the back part of the pillow cover (face down) on to the front, along the same row of stitching, leaving an opening to be able to turn it rightside out. Turn it out, poke the cornes out insert your pillow and close the opening with hidden stitches. Hope that helps!
here is how I made a no sew pillow with piping https://www.charlestoncrafted.com/no-sew-pillow-cover-piping/