10 reasons to use a GIT repository to organize your writing process
1. You can store a complete copy of your work in the cloud and contribute from any device
There are a number of ways to do this and many are free. You can use a laptop, phone or desktop and work on the same set of documents
2. You can create document versions easily
3. You can have a searchable history of what you have written
4. You can collect notes of any file type all in the same place
Including audio files, video, spreadsheets, etc.
5. You can make folder structure templates as branches and reuse them
If you have an organizational template that you like you can save it in a repository and use it to create new projects.
6. You can share your entire project to anyone with a link
Share your work with collaborators and editors and track their comments.
7. You can collaborate easily with an unlimited number of contributors
8. You can open source your project easily
9. Make massive changes to your manuscript as separate branches and then discard them or revert them
Re-order your chapters, rename characters across your entire project, etc.
10. Google docs already work a lot like this
If you don't feel up to managing a Git repository on your own you can start a folder in Google Docs. The revision history is likely to be better than a DIY and you get a lot of benefits from that workflow. You can also start with a folder inside google docs and then create a Git repository later if you want.