Patreon is quite tricky. You basically have to produce a lot of content to convince people that if they invest in you, you will keep making more content.
One trick I’ve seen other people using is to give a reason for people to become your patreon. For example, maybe putting polls of ideas for how the game should evolve, which will give a chance for your patreons to shape the game with you. Or share your latest work and behind the scenes only with patreons. One other idea is to add them in the credits, but that might be too much work.
A tip that is given by patreon itself, is to make sure to have tiers of different budgets, as some users just can’t invest a lot, and others have a big budget and want to influence a project.
Make sure to share all past work you’ve done. When a random person sees you’ve made 10 games before, they are more likely to support you than if you’ve made just the one. You’d also pretty much agree with the idea that it might be months of you putting content out until patreons start joining, but the more patreons you have the easier it is to get more.