

Practice those tasks in a large, already functional open source project. Try to shadow people who already do them. Very relevant link for libreoffice contributors of all kinds
Relevant more general guide (which doesn’t look too out of date) here
Lastly I’ll mention joining organizations adjacent to what you are already excited about working in. I do research code and joined an organization for data scientists in academia. They do regular training and events in things like UI design and documentation.



My gut says capitalism. So I would be extremely interested in examples where:
4-chan isn’t dead, is still pretty open, and doesn’t have a real competitor for what it is. Certain forums and chatrooms would qualify if reddit didn’t exist (but reddit really clearly killed several of these).