I am new to optimizing social media and I have been seeing many references to using Facebook Groups to promote. My fan page is 5+ years old and I have ~10k fans that I have built organically. I have a few questions. How do I post to a group from a fan page? It appears you can only join as an individual Is there a set of best practices for promoting products with groups? Facebook Rules? Is there a directory of groups? What are the best ones to promote my products?