Bias binding can be used to finish off necklines, armholes, hemlines, and many other sewing projects. To make bias binding, it is probably best to read the post How to Make Bias Strips, Piping, and Cording first. Decide how wide you would like your binding to be and mark your fabric on the true bias as illustrated below. I cut my strips 4 cm (1 1/2 in) wide to make these samples, which gives a completed width of 1 cm (1/2 in). Use sharp scissors or a rotary cutter to cut the strips.
Push the point of the strip through a bias tape maker and push the strip through with a pin.
This is my very old bias tape maker.
Start ironing the fabric strip while slowly pulling the bias maker to the opposite side. If you do not have a bias maker, then simply fold the two raw edges evenly over to the center of the strip as you iron.
Fold the strip in half and press flat.
Pin the right side of the strip to the wrong side of the fabric edge. This method is just one of many ways to finish raw edges with bias binding. Choose a method that suits you best. Also, read the post Three Ways To Finish Necklines and Armholes With Bias Binding.
Stitch on the fold of the strip.
Fold the remaining side of the binding to the right side of the fabric. Pin or tack and topstitch in place.
RIGHT SIDE
WRONG SIDE
Shaping Bias Binding and Tape:
To sew bias binding on curved edges, the binding must first be shaped to make the application easier. Shaping can be done with your bias strips or ready-made binding. Use a steam iron and your hand to shape the binding. For necklines or armholes (inward curves), stretch the open edge while pressing the binding and easing in the folded edge. To shape the binding for an outward curve, stretch the folded edge of the binding while easing in the open edge.