I went to an adjunct class once, and the instructor made it seem so simple to go buy a pack of index cards and shuffle them as you see fit. What's not to love about color-coordinating chapters.
The resources for writers are endless, nowadays. On Etsy, these nifty templates set the full book out on a platter. All you really need is a good idea, a pen, and some time (the hardest thing to find). Even if it isn't my favorite option, I'd like them just for my collection of writing paraphernalia.
No matter your preference, all that really matters is that you read, write, and write some more. Tell me what works for you. If you have other resources and outlines, please share what works best for you.