We bought this tool at the Des Moines AQS.
I watched the video and then I used the directions on the tool itself. I had a problem because I used premade blanket binding and it was wider than the tool.
Leave 8 inches of binding, then starting sewing it onto the quilt. Sew binding to quilt and when you are near the end leave a 12 inch space between the starting stitch and the ending stitch. Leave an 8 inch length of binding at the end, (same as beginning).
Look at the quilt so beginning stitch is on your left side. Butt the end of the ruler that is straight against the stitching you ended with, be sure the writing is up on the ruler and have the R facing you.
Lay the binding on top of the ruler and mark a small dot or line where the tool has the mark here line, mark on the edge of the binding opposite the folded edge.
Turn the ruler upside down with the printing up and the letter L should be upright and printing on ruler upside down.
Place the straight edge of the ruler against the stitching where you started the binding. Bring the beginning 8 in tail over the ruler and mark with a small dot or line where the marking line is.
Open the binding and place the letter L on the mark you made on the binding.
Either trace and cut along the tool edge or use the rotary cutter.
Next open the end binding turn tool over and place the R where you made the mark. Trace and cut or use the rotary cutter on the end 8 in tail. I found it easier to press my binding open before I cut.
Place right sides of the tails together and sew 1/4 in seam. Press the seam open and press the binding back to the original fold.
Once I figured it out it worked great.