It’s easy to mock social media, but these are important tools not just for sharing pictures of the food your eating but for informing your colleagues about your research. This article gives a nice overview of how to effectively use tools like Twitter, Facebook, Tumblr, and Pinterest.
Bik HM, Goldstein MC. An Introduction to Social Media for Scientists. PLoS Biol. 2013;11(4):e1001535. doi:10.1371/journal.pbio.1001535. Available in html format.
You can find an earlier version of this page on my blog.