Assemble the Block
1. Sew together one solid white triangle and one solid pink triangle to make a triangle-square (Diagram 1). Press the seam allowance toward the pink triangle. Repeat to make a total of four triangle-squares.
2. Lay out the triangle-squares and remaining squares in three horizontal rows (Diagram 2). Sew together the squares in each row. Press the seam allowances toward the blue or white squares. Then join the rows to make a block (Block Assembly Diagram). Press the seam allowances in one direction.