Interacting on the forums a lot if you include a link to your series in your bio helps a lot, I’ve read and enjoyed a few stories because I saw the creator on here and they were helpful. I think the read for read, sub4sub, and just updated promotion threads aren’t the best for getting up a solid reader amount, as they tend to get people who read and then just stop, subscribe and then just don’t care, etc. I might need to check your story out soon and give some (respectful) feedback. In general threads that are a bit more specific (ie, urban fantasy novels, comics set in the past, stuff like that that give people an idea about your story) will give you more readers. Good luck!