Social Media: What are the guidelines and best practices for developing a social strategy for creative, advertising, and interactive agencies?

Social Media: What are the guidelines and best practices for developing a social strategy for creative, advertising, and interactive agencies?

Majority of popular articles and best practices online present concrete steps on social strategy development for enterprise and client side, but not for agency side. These best practices can naturally be adopted by agencies themselves, but it would be very useful to come up with concrete recommendations on how to develop social strategy for agency side. 

Write an answer on Quora

What are the guidelines and best practices for developing a social strategy for creative, advertising, and interactive agencies?