Although this project is not strictly a quilt - the technique for binding it is exactly the same as that when finishing a quilt.
Cut enough binding strips to go around the entire quilt - and sew them right sides together perpendicular to each other (as shown above)
Sew at a 45 degree angle and trim the excess, leaving just a 1/4" seam allowance - repeat for all binding strips.
Iron a 1/2" flap at start of binding, to give a finished edge, then iron the whole length of the binding in half
Place the raw edge of your binding along the side of your quilt, pin the end in place and start sewing about 8" from this pin - the photo above illustrates where my start is and where I started sewing.
When you get to a corner, stop sewing about 1/4" from the edge - backstitch to finish.
Fold the binding back on itself, as illustrated above.
Then fold the binding down, to allign with the other side of the quilt
Start sewing at the very edge of the quilt and continue down this side of the quilt - repeat for other three corners.
When you get back to the starting point - finish sewing about 8" from the pin that marks the folded end of the quilt
Place the left side of the binding over the finished edge of the binding (where you started)
Flip the binding over, so that you can now see the starting crease of the finished edge you ironed in - mark with a pin - this is where you will sew the binding to make it continuous.
It is much easier to sew the binding accurately, if the quilt is folded in half at this point, as illustrated above.
Sew down the crease - right sides together. Cut seam allowance to 1/4" and press seams open.
Sew the finished binding down onto the quilt...now for the fun, relaxing part - this next step can take a little while, so put the kettle on for a cup of tea, and plant yourself in front of a good movie!
You now need to fold over the finished edge of the quilt, over the raw edge - and hand stitch the folded edge of the binding onto the back of the quilt.
When you get to a corner, continue to hand stitch until you get the machine sewing line
At this point fold the other edge over to make a neat mitred corner
Continue sewing the rest of the binding, until:
Voila! One finished edge!