So, here is what I've been doing for my book. Time will tell if it's effective.

I have the main novel that I completed, but I've also been writing short stories and even some longer ones I've made available for free. I include a link to my novel at the bottom of most of my posts, and even occasionally post announcements directly about my book.

The main thing is to realize marketing a book is one of the most difficult things about self-publishing(which I assume is what you are doing, correct me if I'm wrong). When self marketing, you can't mail it in and expect people to line up to see your book. One of the best methods of generating interest is a teaser, which brings me to my original point. These graphics about dwarven numerals, they don't really get me interested in your universe. That's just me, I'm not much of a language buff, though I am familiar with non standard base number systems. Your few sentences here:

An example is Tahacardor Hadurem Duran which means roughly Stronghelm Three-Axes of the Dhurka Clan. Say "Tahacardor Hadurem Duran" in the most bass and gruff voice you can! Feels Dwarfy does it not? Hahaha!"

That goes much further in generating my interest, at least speaking anecdotally. Creating promotional material that actually gives people a mental image of your fictional world will likely have better results in generating interest than explaining a minute detail of the likely much larger world.

While creating this promotional material, I would also recommend commenting as often as possible. It's hard to do routinely, leaving thoughtful comments on other people's posts, but it really helps people notice your channel and swing by to check your stuff out.