Just sign up already! :D
There are also pre and after activities (but I can't tell much about them since that isn't my style). The German liasons for example have asked character developing questions (like the last: tell the backstory of an supporting character) and more on twitter and do word sprints in November.
This is the text of the last email from NaNo:
Are you ready to unleash your creative superpowers? If you're on the fence about returning to write a novel this November, hop off it!
With pep talks from authors including Roxane Gay, Julie Murphy, and Kevin Kwan; even more stats to help you see your progress as a writer; and 570 active regions running write-ins and other events, this is your year: writers, assemble!
Extend your streak: announce your 2017 NaNo-novel.