The quantity of posts and the amount of times that you put yourself in front of other users on the platform directly correlates to how many followers you will get. Try to post at least two to three times a week at minimum and optimally one to two times a day, if you can.
Ambitious businesses that have great content to share can post up to 10 to 20 times a day, as long as the content is good enough and people are engaging, then you should keep sharing. Make sure to fill out the posts with a nice description, potentially witty or funny sentence or two with hashtags that are relevant.
Hashtags help others find your content and will directly correlate to getting more followers. Hashtags are especially effective if your local area is highlighted in your description, people are looking to follow people in their local area.