In case you didn’t know this (and why would you, really?), books published in KDP can be added to up to 8 additional categories after publication. Many self-publishers will request that their books be added to low-competition categories to try to get their book to the # 1 slot in this category, which will get that book an orange bestseller badge (and the exposure and increased sales that go along with that badge).
This does work, and I have covered it extensively in two of my other self-publishing books (“How to Self-Publish a Book” and “How to Market a Book”).
I am going to advise you not to do that in the case of low-content books, and I’ll tell you why: there is a fairly large amount of f*ckery that has gone on in the past couple of years with people trying to “game” the system to get their low-content books into low-competition categories where they do not belong, just for the purpose of getting exposure for the book and getting one of those orange “bestseller” badges. The theory is that the bestseller badge increases exposure and sales, which actually is true of high-content books, but let’s get real for a second: how many relevant categories can you actually find to put your notebook into? Almost everything is going to be a stretch, which is why Amazon is cracking down. Amazon is all about that customer experience, and finding a notebook in an irrelevant category is not a great experience for anyone.
If you have no idea what I’m talking about, I mean this:
This composition notebook is great, but it does not belong in “Mammal Zoology,” and eventually, Amazon is going to figure that out and remove this book from this category.
Let’s be clear: I’m not saying this publisher intentionally put their book into this strange category just to get this orange bestseller badge. I am saying that if they did, that is not something Amazon appreciates, and this is not something you should be doing, especially as a beginning low-content publisher. I have seen first-hand (in self-publishing Facebook groups) that people are getting their KDP accounts taken away for this sort of thing now, so we are not going down this road with our books (like, at all). I am going to hopefully tell you enough to get Amazon to put your book into decent categories, but not so much that you get yourself in trouble.
One way to get your book into additional categories without emailing Amazon (so, you would keep your hands clean) is to research the categories your competitors are ranking in, then include those categories in your back-end keywords or run ads directly into those categories.
I would recommend Publisher Rocket if you need help picking good categories, but again, go easy on this strategy!!