Reading a book that should appeal to your target market? Share a short quote from it. Share tips for things your clients and customers have already purchased from you. Link to a blog article you wrote, on your website or a guest blog for someone else. Did you just land a brand new client? Announce it, and link to their website if appropriate. Link to a how to article, or share a short how to tip. Build up brownie points with them, and demonstrate you like to help people. Updated your website lately?