How do you structure a large Django project for scalability and maintainability?

When you build a big Django project (like an e-commerce site, social platform, or enterprise app), how do you organize your code, files, and features so that the project stays easy to manage, update, and scale as it grows?

This is a topic that has been discussed multiple times here already. A search through the forum will bring up some threads.

To get you started, see: