However, if you are a writer, joining writer groups and following other writers isn't going to improve your business. I read a lot of writing and technical blogs, but I'm not going to hire any of them to write for me and I don't necessarily want to share their knowledge with my potential customers until they are my real customers. What do you enjoy writing about and who is your audience? Where have you achieved the most success? That is the group of people you want to follow, "share" or retweet to cater to their interests.
If your business is helping shoppers find bargains, be a bargain hunter and share that information with your potential customers. That's the way to show your customer base that you know your business, gain followers in your niche, and direct them to your website.