Here is a free mind mapping tool which maybe useful to anyone undertaking a writing project of any description. The application is called
freemind which is a free multiplatform mind mapping tool which is useful for planning projects and correlating research or personal thoughts and ideas. It's actually very easy to use and the best way to get started would be to watch the collection of videos they have produced explaining the basic functions
available here the tutorials are for an older version but nothing discussed has really changed.
There is an alternative version of freemind called freeplane which is a forked project. Please see the Up Date at the end of this post for more details.
Here is a blog which discusses using freemind as an aid for writing a novel
https://www.spacejock.com.au/PlottingANovel.html. There are other similar blog entries etc. which also talk about using mind mapping techniques for authors planing their work.
There are other free mind mapping package some of which are cloud based.
Xmap is another free multi platform mind mapping tool which is more modern but has limited features in the free version.
Another tool that maybe useful is
ywriter available for Windows only.
When you're trying to work on a novel or another type of large writing project, basic word editing programs just don't cut it. With a typical writing program, you either need to save your novel by individual chapters or as one large chunk of a document. Either way, it's inconvenient and not ideal for organizing your ideas. yWriter simplifies the process of organizing your writing projects.
UP DATE
There is a fork project available from the freemind project which has a much more active development cycle. The application has improved functionality over the freemind version. The fork is called
Freeplane, the documentation isn't the easiest to follow and there are no decent video tutorials available as yet. Much of the information in the freemind tutorials is relevant to the freeplane package which is adequate enough to help beginners get up and running. The community is much more active in the forums also which should help answer most common questions.