If you don't use ads it will be very difficult to reach out and get more of a fan base. I've found Facebook ads to be quite beneficial for the FB groups and clubs I'm a part of. Google Ads may be another way as well, but then again, thats not on facebook, its just spewing ads in a search engine. Keep it simple, throw $20 or whatever you can afford and run an ad for a week or month thru FB. It doesnt hurt to just try it out

Good luck!