Recommendations

I have never had any system design interviews. What are some resources to study and prepare for this type of questions? Anything would be appreciated as I have almost zero knowledge on how to approach this. To be more specific, the interview is for Facebook. I have taken the Software Engineer course a couple of years ago, so I'm not totally oblivious, but the design part was not the focuse of the course (the implementation and team work using the scrum methodology was).