Marketing is scary for solo devs, and reading posts about how we should be doing more of it is also scary. For those of you who've successfully followed advice

Marketing is scary for solo devs, and reading posts about how we should be doing more of it is also scary. For those of you who've successfully followed advice like this (versus myself, where I usually slink right from the comment section back to product development), which modern marketing channels have you found to be the best investment of your time?