Tablecloth with Mitered Corners?

I just made little wraps for my daughters to wear over their flower girl dresses (same basic thing, a large rectangle with border.

Press the corner after you fold it, before you sew and it helps it lay flat. The only thing I had trouble with was how to connect the two ends of the trim to end it. I tried to make a seam but that didn't work out too well. Maybe someone else can help you with that.