When I did my Ribbon Afghan that only had 8 different colors, I planned each color repeat as I went.
|Sorry for bad picture quality|
|You can see the bright red in the middle of the bottom row (where I started) and the bright pink in the middle of the middle row.|
After I finished those 26 stripes, I sat down on my floor, layed the blanket out and sorted the yarn until I chose my next order. Voila! Color repeat number 2!
That might make the blanket wide enough. I might have to add about 5 or 6 stripes after this color repeat. If I do, it'll probably be my favorites that get a 3rd stripe.
This surprisingly took me a while. I was sitting there (you can see my water bottle under the coffee table) and boy was I was indecisive. I am doing rows of 2 and rows of 3 for my granny stripe. If a color was a 3 row color in the first repeat, I was trying to make it a 2 row color, with a few exceptions.
Is this close to how you did your "random" granny stripe?