Are we talking about Chris Timms pattern "Twisted Bargello"?
I have done that pattern and with in the Bargello "run" of fabrics it has more than one gradation from light to dark , this gives it the extra depth and enhances to feel of movement . So ... establish on the pattern the darkest and lightest numbers and then do the gradations on each side of the dark placements , but keep the darkest and the lightest fabrics on the pattern in the same place on your color layout. I found it very helpful to put the order number on the darkest and lightest so when I started moving fabrics around I knew when I had inadvertantly moved one of the key fabrics ( darkest and lightest) out of its position.
It is a fabulous pattern you are going to love the results.