This the long process but don't worry you can increase your followers fast, in insight section of your account you need to check the average time when your followers comes online because if you are posting something but your followers is not online then the post is not going to spread as much as can.

So do post according to your insight section of your account. Second one which is really important, you need to use hashtags.

Like in one post you can use 30 hashtags which is more then good. You need to check which hashtags works well according to your niche.

Like as I am providing staffing solution india, so i will research first about the hashtags which works well in staffing solution and particularly in India.

It's easy but you need to focus on few things and you will see the results one day..!