There had to be a special pocket made for the flags so they wouldn't get creased. Rectangle. The upper side "overlocked". From now on I'll fold the edges before serging at such light fabric. The rest sewn and cut. French seamed.
Then I folded it so that the buttonholes were on the doubled fabric. Then I put two cords inside - they were tied into two rings. When I pull two opposite "stitches" out, it closes and they form a loop for hanging. It's the most comfortable sort of fastening:-)