Do you have plans to build a website soon? There are three major different workflow styles. How to build a website in 2015 from @rukzuk has shown the 3 most popular workflows so that you can pick the style that fits your skills.
For complex products, it's helpful to understand the system at a high level, before anything gets fully designed, prototyped, or built. I like to call this method of flowcharting "wireflowing". It's a hybrid of traditional sitemaps, flowcharts, and wireframes. The benefit is that you can start to make UI-level decisions & establish consistent patterns quickly, while maintaining a relational understanding of how everything fits together.