How do you build community of potential customers?

Once you've identified your target audience, try to meet them on whatever platform they use. Produce content they'll be interested in, make yourself visible by just being actively present on the media, promote your product without being spammy. And build an email database of interested people who are willing to receive news about your work. If you did your research about your audience, you should know more about their consuming behaviors and be able to use your knowledge at your advantage to imply it in your strategy