If you need a social media policy (and every company needs one that has more than a few employees), I suggest two things to get started.
1. Search the net for starter templates. Most social media companies offer suggestions and templates.
2. Check out Stephanie Schwab’s article on social media policies. It’s one of the best articles on the topic of what to consider incorporating into your policy that I’ve come across recently: http://www.socialmediaexplorer.com/social-media-marketing/the-anatomy-of-a-social-media-policy/