Applies to any conference really. You may not need this until next year but you can skim it now and search for it here in 10 months. Also not covered in the article is being a conference volunteer. That is fun and cost effective first GDC experience.
Might be some VFX students who went this year who can add VFX specific notes to the thread. My only advice in that category is go to the Real Time VFX nighttime events, you will be surrounded by the best people in the world while you all get drunk and talk VFX.
GDC Conference Associate (2017 info):
https://www.calounge.com/application.php