For each color you'd like to have in your tartan, select the color and the stitch count. Stitch counts can be anywhere from 2 (the smallest a traditional weaver could do in a 2-over-2-under twill weaving procedure) to 72 (this upper limit is somewhat arbitrary).
You can have up to 120 total stitches in your tartan.
Remember that each stich-and-color combination will be repeated both horizontally and vertically; that's how you get that tartan look!
Stitch counts are always multiples of 2. This, again, is a hearkening back to the way they are woven in real life.
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