NOTE: This is not cheating. In fact, NaNo organisers actually encourage you to do things like this so that you reach your 50,000 words quicker.
1. Chapter Breakdown
This sounds likes your chapter is having an emotional trauma. Well, it is, because you are the one that has to write it and make it as long as you can. After every chapter, try writing a breakdown of your chapter to fully explain what is going on and why some elements of the book are present. This obviously won't be included in the real publication but it will make you see things more clearly before you begin the rest of the book. Plus, it really eats up your word target. I have done this and it has made me think more deeply about where I want the book to lead to and why the tiny details are there.
2. Song lyrics
I thought about doing this today and it is the best idea I have possibly ever had (besides deciding to give writing a novel a go). I have taken a song that relates PERFECTLY to each chapter and pasted the lyrics before the chapter begins. I have put the chapter title, then pasted the lyrics, and have even included which character I would think the song would be sung by and more importantly... who to. Luckily, many of the earlier Ellie Goulding songs just fit in perfectly with my story and I am very happy with how the lyrics are linking to each chapter.
3. Alternative lines
This is one of the funnier things I have turned to in a desperate need for more words. I will think of what a character is going to say, and I write the serious response. Then, I write alternative responses the the same question and try to make them funny. For example:
Question - "Oh my God. Where are we?"
Serious response - "Why would God know any more than you? We have no sense of deities."
A-not-so-serious response - "You are Edward Cullen and you died from food poisoning after eating Bella's placenta. You're welcome."