Comment by jwblackwell

Initially, I just posted my latest product, Quizgecko on HN and then manually DMd a few hundred people on Linkedin etc. That was enough for 100+ users.

I think if you have a relatively novel idea, that is quick to try out, then people will naturally share.

After that, I submitted to various AI tool directories. They drove a bit of traffic and helped Google find the product. Then some landing pages I made started to rank and it has snowballed from there.