As Requested
I'm using a gauge four worsted alpaca wool, and I ABSOLUTELY RECOMMEND using small gauge yarns for this. The finer the better.
If you've got a microscopically fine yarn, or are making something huge, some brilliant soul on ravelry has mapped out this. Which is lovely, but without that eeny yarn only three insignia fit on the average scarf, and even then it's mammoth.
My version is more condensed, and the insignia have been moved closer to mimic the fabric pattern from the film. I may or may not have put far too much thought into this. Oui_je_danse can attest, we spent a zillion hours at weaving works trying different things.
Some notes for beginners with double knit: Printing out both sides of the pattern and gluing them together really helps. When you're knitting the back side of the scarf, you can just flip it over! Remember that each row you complete is also a completed row on the reverse side of the scarf. :)
Don't know how to double knit? This tutorial is super helpful.
And, here's the hastily photochopped pattern:
Front:
Back:
Have fun!