Also, I find it extremely helpful to break NaNo’s daily 1667 down into smaller chunks.
Say, 3 chunks of 500 words.
First chunk: Start with one paragraph of 100 words. Then another, and another. Each paragraph can develop one thought, one POV, one writerly or characterly line of inquiry on a particular thing. Five explicated thoughts later – bam. First chunk. It could be a whole scene.
After three chunks, wrap it up with 167 words of transition; rounding off, or cliffhangering, or developing, or segueing. Stronginthearm’s your uncle, and there’s your 1667 for the day.