About a month ago, a new textbook for the Jinja Kentei was published. This is a manga version of the basic textbook (affiliate link!), and is the textbook for this year’s introductory level exam. I would like to start by saying that it is good, and it should be no problem for people who have passed JLPT N1 to read this; the unusual kanji all have their readings given, and the point of the text is to explain what they mean. If you are JLPT N2 level, I think you could probably manage, although you are likely to need to look up some kanji, and it would be good practice. But it is manga, so you do not face the wall-of-text problem. (This is mentioned as a benefit in the introduction, with Japanese people in mind.) It doesn’t seem to be on Amazon US yet, but Amazon Japan will ship overseas. If you are looking for a reliable and accessible introduction to Shinto in Japanese, it’s a good place to start.
While it is a general introduction to Shinto, it does have a few interesting points. First, because it has been published during the pandemic, it mentions the effect of the pandemic on jinja in a few places. The most interesting is where it tells you how to rinse your hands when there is a flow of water out of a spout, rather than a font and ladle. You rinse both hands together, then cup both of them to bring water to rinse your mouth, and finally rinse both again. There is a note that jinja may have different suggestions, which you should follow, but this is the first time I have seen instructions for this in a Jinja-Honchō-approved publication.
Another interesting point is on offerings on the kamidana. While it does not explicitly say when you should take them down, the phrasing very strongly implies that you should take them down immediately after performing the reverence. That agrees with my considered opinion at the moment, but I wonder whether Jinja Honchō told the author to make that a bit vaguer, to avoid upsetting people who do it differently. (There is a lot of “people say”, “this is different in different regions” throughout the book, as usual.)
(Last year, they published a similar manga summary of the Nihonshoki. That might also be worth a look. And that is also an affiliate link. That one is available on Amazon US (another affiliate link), so this year’s may appear there soon, although in either case it might be worth checking whether it is actually cheaper to get it shipped from Japan. The manga Nihonshoki struck me as a bit less accessible than this book, so it would probably be better to read this one first.)