I’m not sure I can give a precise answer.
Of course, I like to think that what I post is all that good. :)
But there are a few, specific things I did do.
When I began, I became a writer for the publications I could find with the most followers. That got my work in front of many more readers than I could on my own.
I do post a lot, usually multiple pieces per day. That probably helped.
I reply (or try to) for every comment I receive, if only with a heart or a simple thank you. Courtesy counts.
I rarely comment on other people’s work, other than to like it.
I really try to avoid joining in conversations, especially those on controversial topics. Those conversations on Medium often quickly become toxic. I’m a poet, not a pundit.
I don’t promote my work in any way, except occasionally attaching a poem to my Twitter account, but I rarely use Twitter (hive mind) and don’t have many followers there, so I don’t know what effect that has.
This may not be what you were looking for, but it’s all I’ve got.