Hi!
Creating engaging graphs and art for non visual projects can be tricky.
I would recommend creating a set of graphs from a designer to share on social media and forums. Also, mid campaign, for books, you can share the first chapter as a "trial". Some authors do this when launching their books: a video of themselves reading the first chapter.
But since you mentioned than most of your 25% funding came from family and friends, it's important to remember that you should never overlook the online communities: Facebook groups, forums, quora, etc. You have to find thte spaces where your ideal audience is and invest time to talk with this community, give your input, give valuable content. These are the people who will back your project and talk about it to other people.
Create a presence online whenever posible
Good luck with your next project!