1. Identify why you're building the project. Do you want to earn $100,000 in revenue? Build a public profile? Grow an email list for future projects?
2. Determine who exactly your project is for. Is it for investors? Aspiring startup founders? People spying on their competition?
3. Clearly articulate what that audience's major struggle is. Why would they visit transparentstartups.com? How does your site make them better? How does it improve their lives?
4. Cater all your landing page copy to your audience, their primary struggle, and how your site makes them better.
5. Figure out where those people hang out. In your case it's here on HN, Product Hunt, certain Reddit sub-reddits, Slack groups, etc... Find those communities, join, and share your story (you're actually doing a good job in this thread already). Look for ways you can answer questions on the topic of startup revenue, and point people to your site when appropriate.
These 5 initial steps form the foundation for everything that comes after.
If you understand: your motivation, the people you're looking to help, how you're helping them, and where they hang out, you'll have everything you need to start promoting your project.