At a minimum, your social media policy should have the following attributes:
1.) It must comply with applicable laws. While courts and regulators have generally recognized employers' legitimate interests in monitoring employee activity on company social media accounts and from company computers and devices, a few have been found to cross legal lines. For example, the National Labor Relations Board has upheld the right of employees to freely discuss their employment terms and conditions on social media, and applied anti-union-busting laws to disallow restrictions on worker-to-worker communication expressing complaints about working conditions. Prohibitions against such communications via social media have been found to violate the National Labor Relations Act (NLRA), which guarantees employees the right to communicate and engage in other 'concerted activities' for the purpose of… mutual aid or protection" 29 U.S.C., Section 157. The bottom line, "I hate my job" Facebook posts may be protected under federal and state laws where an offensive expression may not be.
2.) Address social media usage both 'on the job' and 'after hours.'
3.) Define and protect confidential or proprietary information. KFC can probably afford to have an employee complain about his or her working conditions. But they'd certainly have to draw the line at any employee who divulged the 11 secret herbs and spices. Your social media policy should clearly define what kinds of information is proprietary and not for public release. Don't rely on being able to make that determination after the fact.
4.) Identify a press or social media point of contact. This individual or department should be the sole public voice of the company or subsidiary on social media. The policy should direct employees to direct inquiries to this individual or office.
5.) Be as specific as possible when describing the kinds of information not to be discussed on social media. Courts have disallowed restrictions that are 'overbroad.'
6.) Define consequences for posting embarrassing material that reflects negatively on the company. For example, there have been a number of cases in which food industry workers took photos or video of themselves contaminating food and posted it online. Your social media policy should make clear that this is a terminating offense, even if they think only a few people will see it.
7.) Consider prohibiting the use of your company's logo, imagery or uniforms on social media accounts. You can also consider instructing employees not to post opinions on controversial subjects without a disclaimer stating that their opinions are their own and do not reflect the position of their employer.
8.) Reserve the right to discipline employees from engaging in illegal activity via social media, such as harassment, stalking or threatening - especially if their employment affiliation is identifiable from the social media account.
9.) Reserve the right to discipline employees for violating intellectual property laws, such as violating copyrights and trademark protections while on social media.