Any advice to get initial traction?

I recently lauched my web app on producthunt. This is my first experience. I am a solopreneur, but I spent 9 months to develop this and worked very hard. I got a few upvotes after the launch and it got buried on the pile with others. What could I have done better? I have the website ready but 0 users to try. How can I attract more users? I would love to hear your experience and expertise.