We have already figured out what reach is and why it inevitably drops.
Regularity. Instagram loves that. Remind your followers of yourself consistently, otherwise, you will find yourself at the very bottom of the general feed. Remember - priority is always given to those whose posts are liked and commented a lot and often. Make a content plan and plan each step in advance.
Likes. Yes, beginning is a shame, but you can't do without it. Although, maybe you can remind your followers to like your post, because they most likely just read your captions. Pay attention to your popular posts and try to replicate your success.
Comments. Encourage your followers to start a discussion or just conversation under your posts. And also be sure to respond to their comments. The Instagram algorithm can cut your reach if you don't communicate with the audience.
Stories. Try to remind about yourself wherever you can. Ideally, post 1-7 stories every day - even a repost of a new publication is considered. Again, encourage followers to engage in dialogue. Polls, quizzes, ask a question - any reaction to your content will bring additional reach.
Hashtags. It is not as effective as it used to be, but they are useful. Put 5-7 hashtags and don't use the same ones in every post. Algorithms may consider this to be spam. If your blog has an interesting section, give it a hashtag and ask your followers to follow it - then they won't miss a new post on this topic.
Text. Add content that is often saved: recipes, lists, instructions, life hacks. Your posts will be added to favorites, it will lead to growing of engagement, so it pushes you higher in the general feed.
Communication. Don't forget about Direct Messages. Provoke a reaction by all available ways - both with hype content and with stickers - a question, yes/no (poll or vote).