Instagram Growth strategies!?

Hi Guys

I have been growing few Instagram accounts for the past 3 months. I use the simple rule of following a certain type of accounts ( depends on the target audience) for two weeks and then unfollow the ones that don't follow me back. Instagram does not allow automation of course and this growth tactic takes a lot of time and the result is slow and steady growth. I am not expecting a miracle but do you have some other useful growth tactic that actually works ( besides the follows, likes and comments, hashtags)? Is there something that I don't know? Thank you. And I also used this article for an inspiration:http://www.colourmesocial.co.uk/instagram-hashtag-growth-strategies-must-implement-2017/