What a glorious thing to do! A great froth of loops and lines of variegated zig-zag stitching. I can see what a wonderful edge this would make.
Whilst this technique produces some really attractive results my colour scheme is possibly a bit too subtle. This is the result of having such a narrow colour range and it might be worth trying to develop a more intense and complex blue so that there's a greater contrast between the blue and the white.