Assemble the Units
1. Layer a print B piece atop a solid black A piece with center marks aligned. Pin the pieces together at the center (see Diagram 1), then at each end.
2. Using slender pins and picking up only a few threads at each position, pin generously in between (see Diagram 2).
3. Sew together the pieces, removing each pin just before your needle reaches it, to make a block unit (see Diagram
3). Press the seam allowance gently toward the print B piece. The pieced unit should measure 4" square, including the seam allowances.
4. Repeat to make a total of 72 block units with assorted print B pieces and solid black A pieces.
5. Repeat step 1 through 3 to make an additional 72 block units using solid black B pieces and assorted print A pieces (see Diagram 4).