Talk to any number of folks including Kristina Halvorson or Joe Pulizzi and they’ll likely tell you the key to any effective social media strategy is a solid and well-planned content strategy.

Content is the engine that drives your social media mother ship. There’s virtually no question about that. The real issue is how do you create, plan and manage your content on a month-to-month basis?

More to the point: How do you build an effective social media editorial calendar?

Here are four simple keys to remember:

* Make sure to include all platforms and channels. As I thought about this post, it seemed a little odd to call it a “social media” editorial calendar. Because really, isn’t it a PR/marketing editorial calendar? You want to make sure you’re pulling content from your existing, more traditional sources: e-newsletter, Web, brochures, and other media. They key is repurposing the content. Finding a new angle. And, making that angle compelling for the unique audience you’re targeting.

* Focus on quality over quantity. Yes, you want some degree of consistency and regularity in your social media content–but not at the expense of quality. Yes, you want to plan for multiple posts per week on platforms like blogs and Facebook–but not if it means throwing out staid or re-hashed thoughts or ideas. Make sure your posts and updates are unique. Compelling. Interesting. Insightful. Anything less will do more harm than good in the long run.

* Don’t forget about your audience. Not all platforms allow for this approach (Twitter, for one), but keep your audience in mind when considering content sources. Customers make great guest bloggers. Partners can add substantial credibility with a post on your Facebook wall. Whatever the case, don’t forget about the many audiences you target–and think about how they can help you tell and share your story online.

* Questions, polls and collaboration. Remember, social media is all about two-way conversations. No better way to do that than to start with a question. Poll your audience on Facebook or Twitter. End your blog posts with a question from time to time to get the discussion going. Ask your viewers for their thoughts in your next video on YouTube. Whatever the case, ask your key audiences what they think. And, make sure to use that information in upcoming posts and updates.

Note: Photo courtesy of Romulo Castillho via FlickR Creative Commons.