If you use binding that is 1.25" wide, this will work perfectly.
Start a few (3 or so) inches from the end of your binding.
This is a view from the side looking to the back of my machine to show you how far in I'm starting.
Using a good eye or a quarter inch foot, sew down the first side of your project. STOP when you come to within .25 of an inch away from the edge of your project, with your needle in the down position.
The scissors are pointing to the mark on my quarter inch foot that tells me I'm .25 away from the edge.
Lift up your presser foot.
Turn your project a quarter of a turn.
Lower your presser foot and sew in REVERSE to the rear edge of your project. Lift your presser foot and bring your project a little closer to you. Don't bother cutting thread.
Fold the binding back to make a 45 degree fold, nice and square like this . . .
Hold this fold in place as you bring the remainder of your binding down over top of it. Make sure everything is nice and square.
Holding this folded corner in place, put it back under your presser foot, right at the edge, lower your presser foot, and sew to the other corner where you'll repeat this process.
Stop to smooch the princess that found you in your sewing room when looking for her good-morning pets.
When you get two inches or so away from where you started, STOP.
This photo just shows you the room you have in between where you started and were you'll stop.
Bring one end of the binding about half way into that space and fold it down. Then bring the other end of the binding and fold it to meet the first.
You can either touch this with an iron, or finger press, or I prefer the 'dig in with your finger nail' approach.
Pin the binding together a few inches away from where your creases are.
I draw a very faint line just barely above the creases. This helps me see where there crease is. Put this in your machine and line it up so your needle is just to the left of the line you drew, which should also be exactly where your creases are.
Sew across and you end up with this.
Trim the excess down to .25 inch.
(Not sure what I was thinking here, that must be .5 or .75 of an inch I left there!)
Finger press the seam allowance open.
(Or use the previously mentioned nail-dig technique)
Don't let the second seam allowance at the top of this photo throw you. That's simply where I had to piece strips together for my binding.
Now, load this back into your machine and sew this section of binding on to your project.
Once this is done and you flip your binding out, this is what you have.
And here is what those corners look like.
Next up? Binding a Quilt Part 2: The Hand Work!