There are many ways to end a binding, but I like this method because it's easy and you can make sure the binding fits correctly before cutting. This method works with binding that has been pressed in half. Note: I used to cut my bindings 2 1/2 " wide to make finished 1/4" wide bindings, but now I cut them 3" wide to make 1/2" wide bindings because it is so much easier!
Step 1 When sewing on your binding, leave about 8" unsewn at the beginning and stop sewing about 12" before you reach the end where you began sewing. You need this much wiggle room for maneuvers.
Step 2 Arrange your quilt nice and flat on a surface and fold up your bindings somewhere in the middle of the unsewn portion to see where they meet. Be sure to allow a tail on your bindings at least the cut width of your binding. More is better. Do this where there are no binding joins so there are not too many seams in one place. Using good scissors clip through the bindings as shown in the picture. Make your clip smaller than your seam allowance, but big enough to see when you open up the bindings. These tiny clips show where edges should meet.
Step 3 Open up the binding on the right with your right hand......
Step 4 and turn your hand over as shown. Now the right side of the binding is facing you and is oriented correctly for sewing.
Step 5 Open up the binding on the left hand side and lay it face down on the other binding matching up the little clips. The clips are too small to see so I've indicated where they are with the little green arrows. At this step you are going to feel that the binding is too short, but it's not. This is where the 12" opening helps give you "room to move". Put in a couple of pins to keep the fabric oriented correctly.
Step 6 Then sew from the upper left corner of the binding to the lower right corner as indicated by the green line.
Step 7 Sewn
Step 8 Check to make sure the binding fits nicely , then trim away the excess fabric and finish sewing the binding to the top. That's it!