You should be using Instagram, but have you ever wondered how it works.?  SEO is basically just making content that is optimized for search engines.  Instagram is a search engine for photos (not really, but kinda). If you understand how it works, you can get an idea of to craft your content.

Recently in a tech crunch interview Instagram revealed how their feed system actually works.  As you might guess it's a bit of machine learning with a lot of weight based on how you interact with the content.  If you watch more videos, then you'll see more videos, for example.   They revealed 6 key categories that are used as metrics.

https://4rdmarketing.com/6-keys-to-how-to-dominate-instagram-feeds/