1 Start by drawing a short line with the pencil tool. Make the SymmetryWorks pattern of the type Perpendicular mirrors & glide (cmm). Suitably increase the size of the control path.
2 Complete the contour interactively using the pen or pencil tool. Of course, you draw only the highlighted part and the plug-in provides the rest.
3 Copy the pattern to another window. Expand it. Pick the neighboring lines that make up the contour of one of the "jigsaw" pieces and discard the rest. Join the lines of the contour. Apply a fill color.
4 Replace the highlighted line created in step 2 with the solid piece in step 3. Optionally add the squares for ornamentation.
5 Expand the pattern. Apply a darker fill color to every other interlocking piece.