As with yesterday's exercise of revisiting the physical world, today is the day to revisit the cultures and societies of your world.
Start big: Do you know the major political and social groups in your world? Where do they live? How are they similar? In what ways do they vary? What values do they hold most dear? Are they also racial groups, and if so, how do they differ physically from each other?
Then narrow it down to a smaller region: Who are the people in your main characters' homeland(s)? What's important to them? What language do they speak? What kind of industry do they have, and what kind of food production do they have? What factions exist, and where does your protagonist fit into the factions? What is the primary unit of money called, and what can it buy?
Even smaller: What is a typical town, city, or settlement like? What was your protagonist's home town like? Does it change over the course of the novel? Who does your protagonist know from home, and what kinds of relationships does he or she have? How was the protagonist educated? Has he or she ever left home before?
Even smaller: What is a typical family structure like for your setting, and is it different in different parts of the world or for different factions? What is your protagonist's family like? Is that typical for where he or she is from, and if different, how? What other role models within the family or in close friendships does your protagonist have?
After 15 minutes of revisiting your notes with these kinds of questions in mind, you will have a good idea of any gaps in your background knowledge, and where you might need to change a few details (some major, hopefully most will be minor) to make everything more consistent. Remember: it's all right to have gaps, even at the end of this month. The process of writing the story will help you fill in the gaps and make a more coherent novel.