Listing is a brainstorming technique many people find useful. It means doing just what its name suggests -- listing possible topics and then sublists of things you could say about each topic. A list could consist of the main topic of regional dialects and then sublists would be regional dialects you know or have experienced. Additional sublists might be particular words of each of those dialects, things you have noticed about those dialects (i.e. New Yorkers speak fast), what you think those dialects sound like, etc.