If you have a blog, you NEED to be on Pinterest as much as need to be on social media. It has such a huge exposure to an audience that not only gets your content in front of the right people, but gets them to click through to your site, re-pin your content, and sign up for your e-mail list if you have an opt-in. One common myth I like to debunk is that Pinterest is actually a search engine, not a social media platform. It loves keywords, descriptions and images.
