I looked at it like it was a paper-pieced pattern and here's my best shot. [#] corresponds to the numbers on the template pieces
1) Sew two  together (or fold fabric before cutting)
2) Sew  to each side of the  unit
3) Sew two  together (or fold fabric before cutting)
4) Sew  on each side of [1/2] unit
5) Sew  on each of 
6) Sew  on left side of [6/8] unit
7) Sew  on right side of [6/9/5] unit
8) Sew  to 
9) Sew [6/8/5/4] unit to each side of [2/7] unit
10) Sew [6/8/5/4/2/7] unit to each side of [1/2/3] unit
Or you could enlarge the tempate diagram and treat itlike a paper piecing pattern.
I think it's gorgeous. I may just have to try it. Thanks.