To determine how life might be lived in a culture with a much different level of technology, Elliott recommends studying a book on the life of a pioneer woman, or spending time in a developing country to observe how people live. No human society is monolithic. Flaws are as interesting as strengths, and the richness of culture lies in the ways flaws and strengths interact. If you've set up your culture believably enough, eventually the characters will simply begin to act 'in character' to their society. However, too much detail becomes a mass of undifferentiated background that blurs into a porridge in which nothing is highlighted.
Characters can serve to introduce readers to the writer's world.
Or, imagine the reader as an infant, who must have things defined, not necessarily all at once, but gradually over the course of the narrative. Otherwise, the world is unintelligible. As a writer, I can introduce the culture bit by bit to the reader as the Outsider comes to know and understand, or misunderstand, the society. In the Jaran novels, Elliott uses the very different characters of Tess and Jiroannes to highlight the culture from both perspectives. In The Law of Becoming , Jiroannes' culture-blindness adds an extra layer, since his misunderstanding of jaran culture also reveals a great deal about his birth culture through the assumptions he makes, the way he dresses and has himself cared for, and through the people he surrounds himself with and how he relates to them.