1. Sew a medium or dark print 1×18" strip to one edge of a blue stripe 1-1⁄2" square (Diagram 1). Press seam away from blue stripe square and trim strip even with edge of square. Sew trimmed medium or dark print strip to opposite edge of blue stripe square. Press as before and trim even with edge of square (Diagram 2). Set aside remaining trimmed medium or dark print strip for use in other blocks.
2. In the same manner, sew a light print 1×18" strip to remaining edges of Step 1 blue stripe square. Press seams away from blue stripe square. Trim as before to make a block center (Diagram 3). The block center should be 2-1⁄2" square including seam allowances; square up, if necessary. Set aside remaining light print strip for use in other blocks.
3. Continue adding assorted medium/dark print strips and assorted light print strips to block center as before, pressing all seams away from block center and squaring up after each round, if necessary, to make Block A (Diagram 4). Block A should be 5-1⁄2" square including seam allowances.
4. Repeat steps 1–3 to make three A blocks total.
5. Reversing the placement of light and medium or dark prints, repeat steps 1–3 to make three B blocks.