[alook]

Look at some good open source projects, and look at the overall project/module structure as well as the OO graph.

Re: high-level project layout: - where are their build files? - how are the source packages broken up? - where are the tests stored?

Trace back from the entry point to the code and look at how things are encapsulated, where code gets re-used.

Diagramming out with something like UML is cumbersome but can be helpful to visualize the structure as you're getting started.

Looking at software design patterns (while often overkill) can give you a good sense for some common ways people try to re-use code. For example: - https://en.wikipedia.org/wiki/Design_Patterns#Patterns_by_Ty...

[rhoursour]

A good place to start would this repo that outlines some popular folder structure conventions: https://github.com/kriasoft/Folder-Structure-Conventions