I heard from a lady, Steemian, she had 3 accounts very active and published, what you have to do first is publishing some books (9000 or 12500 words) you can refer to that seems to work.

I also know someone who for a longer time gave away one free ebook per month. It was a way to attract customers.

It's cheaper to let some friends read and read your own text back after 1 day, next 3 days and one week later. Reading out loud helps as well.