When I was done with this block I realized that I'd used this fabric in another block already. Since my plan is to use 225 different fabrics, I suppose I'll be redoing this one at some point.
Print or trace the block diagram onto foundation paper, number, and cut out as in the photo.
Foundation piece the numbered sections and trim the seam allowances to ¼". Cut the unnumbered pieces out of fabric, leaving a ¼" seam allowance.
Sew the two center sections together. (Note that they're laid out incorrectly in the above photo.)
Sew the pieced triangles to the resulting section.
Attach the non-pieced triangles.