In my opinion, there is no one-size-fits-all approach, but I think that if you show genuine interest in their challenges, and provide real added value, you're heading in the right direction. Would love to learn from you as well! What have you been doing so far to grow your community?
As many have already mentioned - real value (what specifically it's going to mean in your case will depend on your project).
Also, be ready to allocate a significant chunk of your time to it, speaking from experience.