//01 Grammar & spelling:
It is such a simple thing but I have seen people have basic spelling mistakes or sentences simply make no sense on business accounts. Always check before posting anything. It is how you are portraying your business to the world. If you or the person managing the account doesn't always pick it up use spell check or something like grammarly.
//02 Quality of Images:
Screen shots from google search, blurry images or they simply don't fit the grid so when you look at it on your profile you can't make out words fully. Good lighting and a good camera is a basic. Luckily a lot of good phones these days can be just as good so you don't always need to spend a lot of money on a professional camera. Take a clear picture which isn't too busy or takes away the focus from what you want to show off.
//03 Use of hashtags:
Always search the results of hashtags before using them. Make sure none of them are banned and look for results that don't have a ridiculous amount of images. It will be too easy to get lost in the noise. Instead go for some smaller hashtags that can reach your ideal audience. If you use them in your stories then shrink them down and hide them behind a gif or some text.
//04 Engage & reply:
I'm not sure why but sometimes I see small businesses not replying to comments on images, answering questions or they ignore inbox messages. It makes you look like you don't care about your customers and can deter poeple from using you again. Always reply to questions and messages, say thank you for nice comments and reply to inbox messages. It doesn't take a lot of time and really shows the customers that they are important to you and your business.
//05 Make stories your own:
You can use the simple copy and paste system on your phone to copy images and add them into your stories so you can add logos on your story or have more than one image one there. Use the tools given by instagram to engage with your followers. There is poll, questions and so much more to engage and get some research on what they want so you can promote to them better. It gives your stories something different and a way for your audience and customers to get more involved.