What's a good way to have a storyline well-organized in your head?

[CephCepherson]

Hi there, for the past few months I've been thinking on and off about a specific scenario that I believe I could write as a novel. While I do get many solid ideas about it and I've already begun to conceptualize initial chapters, I struggle with really finding a red thread for the story as I am unable to really explain what's going on without delving too far. Should I maybe put everything in a mindmap to make it easier for me to build onto a foundation or are there any other ways of getting proficient enough in storyboarding that it starts to make sense? Thanks!