I had the quilt that I am getting ready for the frame draped over it and thought that I needed to move it to the floor to measure the borders. Then I thought... do it right where it is.
I made sure it was nice and straight across the center bar, smoothed it all out, and layed the first border strip across it. I pinned on one end (after squaring up that side of the border), smoothed it across, pinned it and made a tiny snip with the scissors. I stuck a pin in by the snip so I could find it when I moved it to the sewing room to cut it square. I then used that strip to cut the other one.
This picture is doing the other two sides after sewing on the first two. Really nice to just bring up the edge of the quilt and stand or sit to pin the borders on while the whole quilt can be layed out straight.