I would have to find the magazine to give you the full details. That might take me quite some time as I have moved house and reorganised the sewing room since I made this quilt. so I have made a drawing and will load it as a set of photos.
STEP 1 You start with a small white/off white square. then you add a blue rectangle to each side and then trim. as in first photo.
STEP 2 Add another 4 rectangles, one to each side and trim again.
Then add 4 large triangles one to each side ( or you can do the rectangle thing again)
STEP 3 Slice large square through the middle in horizontal and vertical directions and you now have 4 basic units and lost of triangles left over to make more square ina square blosk for another project.
I hope that helps.
Take one white square and add four blue rectangles. Then trim along red line.
Then add 4 large blue triangles (or you could do the rectangle thing again.) Bisect the block from left to right and top to bottom. along red lines and finally you have 4 identical basic blocks. Well the drawing is a bit off square but you can see the basic principle I hope.