I agree with jljack. I have seen many variations of log cabin quilts. And I have made them with purple centers, green centers, and red centers. Traditionally a red center stood for the hearth, or heart, of the home. It represented the love and warmth inside. From there you normally do 3 - 5 rounds of strips. Size and number of rounds will determine your block size, or decide how big you want your blocks to be, divide by the number of rounds and that will determine your strip width.
Did I explain this OK?