Having now done this quilt 3 times, I'm fairly confident that it's all sorted. The first one I was hacking up my fabric randomly, making it up as I went along, the second time was a bit better, and the third time it all came together flawlessly. The instructions for a quilt cut from yardage come to approximately 135cm, one made using a layer cake will be approximately 155cm, with a narrower border than shown.
If you are cutting all the fabrics yourself, first you will need 36 rectangles measuring 20x10cm (4x8") I cut these from 18 fabrics, and used the rest of the width of the fabric to cut a strip to make a scrappy binding, but it could be done with less fabrics - if you have twelve prints cut three of each, if you have nine, cut four from each.
From 1.8m (2 yards) of solid background fabric, first cut across the width of the fabric five strips 20cm (8") wide, then cut these strips into 25 squares, five across the width of the fabric.
Next, cut 2 strips 30cm (12") wide, then cut these into 6 squares, 3 across the width of the fabric. From the edges of the strips, cut six 10cm (4") squares.
From the remainder of the fabric, cut four squares of 16cm (6.5") and six more 10cm (4") squares.
Finally, cut your 30cm (12") squares and your 16cm (6.5") squares into HSTs.
If you are using layer cakes, you will need at least 18 squares of print (cut in half) and 34 squares of solid - 25 remain whole, six are cut in half into twelve HSTs and three are quartered into 5" squares.
Lay your prints out or up on your design wall to get a layout you like. I just put mine randomly.
Add the little squares in the corners.
Add the big squares in the gaps, as well as one at the outside of every print.
Sew the pieces together into diagonal rows and press the seams. There will be two pieces at either edge that wont be sewn yet.
Sew the rows into pairs with their neighbour of the same length. The centre row will remain on it's own. Press the seams
Attach a large HST to the ends of each row, with the right angle matching the edge of the printed fabric. There will be a slight overhang on the edge of the solid fabric. Trim this off after pressing. If you are using Layer Cakes, the opposite will happen - the triangle will not reach to the edge of the strip. The jagged edges left over by the original squares will be trimmed down after the top is completed.
Sew all your rows together and press the seams. If you are using Layer Cakes, trim the points from the edges - the squares in the corners should contain enough fabric to be trimmed to right angles at the same line as the low edges of the HSTs.
Sew the remaining four HSTs to the corners.
I haven't yet made a back or quilted mine, but I'll update with some photos when I do.