I square the quilt up and then I pin baste it, quilt it, and then trim the three layers neatly.
Then I use the longest straight stitch and sew about 1/8 inch from the edge to keep all the layers together.
I pin and then machine baste the edges of the binding together before attaching it to the quilt.
I do not press the binding in half because - when it gets folded a few times, the "center crease" is off by a few threads.
I like to sew the edges of the quilt before putting the binding on because then I don't need to think about whether I have all the layers included.