Assemble the Block
1. Sew together one light blue print small triangle and one dark blue print small triangle to make a triangle-square (Diagram 1). Press the seam allowance toward the dark blue triangle. The triangle-square should measure 2-1⁄2" square, including the seam allowances. Repeat to make a total of 13 triangle-squares.
2. Lay out the 13 triangle-squares, three light blue print small triangles, and three dark blue print small triangles in five horizontal rows (Diagram 2). Sew together the pieces in each row. Press the seam allowances in one direction, alternating the direction with each row. Then join the rows. Press the seam allowances in one direction.
3. Add a red print large triangle to each long edge of the pieced unit to make a block (Block Assembly Diagram).