There's a little bit of maths in all patchwork projects. This time it was as simple as dividing the required length and width of the finished piece to work out what size squares to cut. I decided on 9 across and 13 down using 7 inch squares. I was using fabric from my stash, so then I started measuring and cutting until I had enough.
Next I spread all the pieces out on the floor to decide on placement. But I needed a way to keep track of the order while I stitched everything together. Keeping it simple--just a safety pin and a scrap of paper to mark each row.