Ask HN: What is your repeatable marketing process?

For those of you who're launched and growing, what have you discovered to have worked to acquire customers and decided to double-down on it?

Is it cold email, social media outreach, content marketing, PR/publicity, forum signatures, "Powered by" backlinks, affiliate marketing, perhaps some guerrilla marketing tactic?

What has worked best for you that you're still executing the crap out of that blueprint to grow and grow?

I'm curious because I just recently launched my app (https://zlappo.com), and I'm looking for ideas on how to market it.