I recently finished (watching) an InDesign tutorial on YouTube that I've been meaning to get around to for some time now. I have prior experience with some ANCIENT page layout software, like... the company has been out of business for such a long time that their replacements are out of business too, and was delighted to learn that in spite of decades, REMARKABLY LITTLE HAS CHANGED IN PUBLISHING SOFTWARE.
Of course I still have to do all the work of laying out the pages for my book, but that will be easier since most of the content is done. I can certainly borrow layout concepts from published RPGs... I certainly have a lot of them on my shelf for quick comparison.
Then there's the getting around to actually doing it, but I'm pretty motivated.