The best way to find board members is to find people in your industry (or market) that show signs of being someone who would enjoy being on your board. These are typically people who

1) Are on other boards similar to the kind of organization you're starting
2) Are part of organizations that give back to the community
3) Publicly display that they are charitable and give back.

Using those filters, then you'll want to find people who have the right type of experience that will help you where you need. Ex: Operations, Fund Raising, Marketing, etc.

The best way to get started is to find someone who's done it before and ask them directly (wink wink). Here's a list of people we like: https://clarity.fm/browse/funding/nonprofit/s/best-match/f/all