Without sounding pretentious, I run a hair instagram account with well over 200,000 followers and have spent countless hours researching social media.
The first thing to consider is your audience. There is ZERO benefit to having 1000 followers that live half way across the globe. It is quality NOT quantity.
Second thing is engagment. SM platforms not show posts in order of engagment NOT time posted. This means if they show your post to 100 people and and only 10 people like it, the post will die. So if you want to encrease engagment give people 'engaging content' 1) great photos 2) viral trends - e.g high conrast ombre, seamless blending/ ice blondes. 3) encourage commenting on posts.
The last thing is branding. Create an artfully co-ordinated portfolio that doesn't just include hair photos. Your brand is the experience that you are selling, be a 'cool' brand.