I finally got the left-hand end of the yellow birds finished and sewn on.
This leaves me with something about 60" wide, but only about 50" high, so I am going to add on to the top and the bottom, until it is nearer to square.
I am going to use up some of the extra flying geese units, and a couple of pockets, and little bits and pieces to get things all the same size.
This gives you the general idea, though obviously I need to level off the bottom and the orange-y strip isn't sewn on at the top, so it won't be quite that wide. Some of my geese are much smaller than others, but rather than wasting them I am sewing them into pairs and then adding scraps across the bottom - the two in the left-hand corner are trimmed down already. I think this will all look okay once it's done.