When attaching binding (bias or straight) to an edge that is continuous, it is often desirable to avoid bulk where possible in the joining of individual pieces. This occurs when there is too little length in your fabric to avoid piecing. The typical way to join the short pieces to make one long piece is to cut each end at a 45 degree angle and stitch the angled ends together. The can be accomplished in a variety of ways. My favorite is to start with the ends squared off as if you were going to simply sew a seam at a 90 degree angle to the length of the binding. Then I lay the two pieces right sides together at a 90 degree angle and stitch across the diagonal of the square formed. NOTE: pin along the proposed stitching line and open it out to make sure you are sewing the CORRECT diagonal. One makes a miter which is not desired here. The other diagonal is the correct one. You can start in one corner, take a few stitches, and then hold the thread tale in the direction you are sewing so that it forms a visible diagonal to follow as you stitch. Then just cut off the excess triangles on each piece.
If you are attaching the binding to a piece that is continuous in that it does not have a specific start and end place, then it is also desirable to attach the beginning and ending of the binding in a similar diagonal manner. This is important, for example, when you are binding a quilt, or even the outer edge of a jacket when the finished edge runs along the hem, front edges and neckline. Simply sewing the two ends together in at a 90 degree angle from the length of the binding creates a lot of bulk and is also a fairly weak seam.
To join these two pieces in a perfect diagonal, first begin sewing with a generous tail left over at the beginning, say around 7”. Then sew around the object to within about 10” of the beginning of your sewing. Remove the piece from your sewing machine. Now you need only measure the width of the binding piece. This is the amount of overlap you'll need for the perfect diagonal (curly braces in figure 2). For example, if your binding starts out as 2” wide, then the overlap between the beginning of the binding and the end should be exactly 2”. Once you have the overlap cut precisely, then fold one end at a right angle and finger press. Slide the other piece under it. It is now possible to see where the diagonal stitch will go. You may wish to mark it with a pencil or, as indicated above, use the thread tail on your sewing machine to guide you to a perfect 45 degree angle. Finished join should look like the drawing below. You can now finish attaching the binding to the piece, fold and finish as you normally do with a binding.See you next time, Martha