Making Binding with the Quick Trim ruler

I recently purchased a "Quick Trim and Circle"  ruler from Creative Grids as part of a Block of the Month class I am taking.

Using the white lines on the ruler you can cut half square triangles with the seam allowances already built in.  No need to mark those pesky diagonal lines!  We have been using it in class to make flying geese units, but I have found it a really handy tool for joining binding strips.   Here's how it works:

Start by placing a pair of  2 1/4 inch strips right sides together at a 90 degree angle.  (I use the cutting lines on my cutting mat to make sure the strips are straight.)

Position the ruler over the fabric.  The white lines should follow the top edge of the horizontal strip, and the right edge of the vertical strip.

Cut.

Place a couple of pins to keep the strips in place.

I find that it saves time to  cut and pin a series of joins before bringing the whole thing over to the sewing machine.

At the sewing machine, sew a quarter inch seam.

When you open up the joined strips, you will have a continuous piece of binding strip ready for your project.

Press the seams open to avoid bulk.

Done!

UPDATE:
I woke up this morning, and realized that, being left handed, my approach to cutting with this ruler might seem opposite for a right handed person. Thankfully, the ruler has lines which can be used for either a right handed or left handed cut.  Here is the way a right handed person would use the ruler.  The white lines should be lined up with the top edge of the horizontal strip, and the left edge of the vertical strip.