If your business has a Twitter account, you should be adding new and different content frequently to your feed. This is a great way to simply acknowledge your fans or give them business related information. Your followers will stay interested in your tweets if you occasionally offer them business promotions through them.
When using social media marketing, you should offer your followers special offers. Followers will be more inclined to purchase from you when you give them exclusive discounts on your products or services. Try giving them a fun contest to participate in that will allow them to receive a special promotion or discount. Use social media sites to share exclusive information with your followers as well.