In the Winter issue of Interweave Knits, Vicki Square shared her thoughts on designing with and creating your own motifs in The Thinking Knitter, page 20. But there's always more to explore with motif shape, line, and color:

Geometric motifs lend themselves so well to knitting, with their straight lines and sharp corners. I am currently designing a kimono with an all over repeating motif inspired by Japanese shibori dyeing (http://en.wikipedia.org/wiki/Shibori) techniques: It is a concentric squares idea with a pin-dot of color in the center of the square, reminiscent of a rice kernel secured with thread in silk fabric before dyeing. I want a fine proportion to each square, with just a single line of stitches forming each one, and a single stitch as the center dot. Two colors and the stranded technique with a bamboo yarn gave me the fluid knitted fabric I envisioned.

The role of color in this design scenario has to be bold enough to present the motif with clarity. With just a single line of color to define my squares, the motif would get lost if the colors were too close in hue or value. When motifs use a larger block of stitches, with more than a single line of stitches, more subtle colors may be used with no loss of definition. For example, a solid maroon yarn and a coordinating marled yarn of maroon, brown, and black could only be paired successfully with motif areas that are large enough to differentiate the pattern. These colors were too close in value for my shibori design, but a soft lilac and maroon worked because the individual squares were more evident with the value variance.

When a motif calls my name, I choose a color palette to display it to best advantage. I consider the overall feeling my color choice makes, whether bold or subtle. And then, I want my knitting time to count. After all, who wants to put in all the time and effort to knit an exquisite motif that won't show?