[imhoguy]

What still works, but ofc depends on what you've made, is to reduce signup friction to minimum or skip it if you don't need user info. Then ensure the data you produce is easily shareable and by the network effect your users can market your service. To bootstrap initial spark you need to share these links yourself in communities which would be interested in your data. Please don't spam. Obviously converting freeloaders into customers is another book to learn.