There are a couple of ways to make bias binding and for the floor pillow project I used them both. Here is my preferred method of making the bias binding:
This is the fabric that was left over after making cutting out the pillow front and back. I was luck to have such a large piece to work with. I cut a piece that was approximately 20" x 30" and made sure that the corners are 90 degrees.
Here I'm getting ready to mark a 45 degree line on the fabric. For this particular project, I'm using a pencil. If this was for clothing, I would not use a pencil but chalk.
Here the line drawn on the fabric.
Here I have carefully cut down the drawn line.
Now, place the right sides of the edges together and stitch a 1/4" seam. Press the seam to the side.
Here is the results.
Here I've drawn the cutting lines using a straight edge. It's important to be very accurate here.
Now, offset the by one set of lines and pin matching the the drawn lines at a 1/4" seam line. Again, it is very important to match at the seam line. Also, pin at every line. Sew a 1/4" seam.
Here are the results of sewing. I haven't pressed the seam in this picture. I waited until I have cut out the bias strips. Cut out the strips and wrap around your cording and baste in place.
Here's the finished picture of the pillow with the bias piping on the edge. Sorry, I forgot to take a picture of the bias strip or the cording upon completion.
I picked up this technique somewhere in a quilting class or a quilting book but it works for every situation that you need a woven bias binding.