While you can find lots of tutorials on creating your own bias binding, I’ll go ahead and give a little tutorial of how I created mine for use as trim detail on the armholes and neckline of the polka-dotted dress.
First, I cut a piece of fabric 16″x16″. (You may think this won’t create much bias trim but you would be wrong! Ha ha. It created at least a couple of yards for me. I used it for the armhole trims and neckline trims of my dress, and I still have lots left over.)
The top and btm edges should be noted in some way –I used blue pins on the top and bottom– and then the two sides should be noted differently — I used yellow pins. Cut the square piece of fabric diagonally in half. (Step 1 below)