I just contacted an indie game studio building a game my community enjoys. Seeing if we want to mutually share links back and forth to help promote each other at no cost to either of us (since well, indie studios usually don't have a lot of budget for advertising/marketing). The game itself is a fun little single-player dinosaur ranching simulator. I feel it'd be an excellent choice for partnering up.
Once I have a job, I'll do some more events with rewards like gift cards, but as of right now, I have literally zero income so that's not possible at the moment.
I do write my blog posts on my site with an SEO focus where I can, but also not "keyword stuffing," which is also bad.
I've looked into Reddit. Most dinosaur-related subreddits seem to not allow self promotion at all, so unfortunately, that's kinda outta the question for me.