In order to Nano you have to be able to write pretty damn productively, if not necessarily very fast. Seeing as you are most likely still doing a job or studying for an exam or something else at the same time.
Kevin J. Anderson to the rescue:
“Okay, I’m a prolific author. Over the next few days, I’ll be re-posting some of the tips I’ve compiled over the years. If you find yourself flagging, or looking for new ways to increase your productivity, I hope some of these help.”
Read Kevin J. Anderson’s productivity tips for Nanowrimo here