I made a King size quilt for my son, using Horse material like this. I used a 36" X 36" panel of the material for the center.
I did a quilt as you go method and quilted along some of the lines of the blocks. When I ended up, I had a big square.
I then cut 15" strips of other horse related fabric, drew me some lines for quilting ending up with long quilted strips. I then attached these to the center square by adding long strips of fabric to the back of each. Brought the joining strips to the front and folded one to the left and one to the right and stitched them down. It turned out more than just breath taking if I do say so myself......I grafted it all out on graph paper first.
don't forget to add your 1/4" seam allowance to what you cut.
For my joining strips, I cut those at 2 1/2".........kw