I almost always do a bias binding and I don't press at all. I match raw edges when I sew it to the back of the quilt, flip it to the front and use my zipper foot to sew it to the front of the quilt. I hold a couple inches in place with my hands(no pins or clips) keeping the edge of the binding right at the seam. Using a zipper foot helps me keep the binding right where I want it and my stitches right at the edge where they should be.
Cari