I find that it's easier for me to complete a novella when I first organize my thoughts on paper.
(Sorry for the mirror image--that's what Photobooth coughs out)
I don't edit my thoughts or think about the grammar. I just write and write and write. The day after, I transfer the words on my computer. Sometimes, I don't even have to look at my notes because they're all in my head, and I now have a clearer, more succinct version that flows from my fingertips.
I guess it's because I'd already purged my brain of all unnecessary plot elements that I'm able to get a more accurate feel of what the story is all about.
How about you? What's your technique?