Yes, my advice for writing your short book would be to sit down and write a novel outline (which is different from an essay outline -- more like a wordy description of the important stuff that happens in your book). Then if you feel like you need more structure, you might break the outline up into scenes, and write down what each scene accomplishes (does it develop character? move the plot? provide necessary background information? etc). Sit down and write it all the way through without going back to edit, and keep writing even if you think everything you're writing sucks. Then put it away for a few weeks or a couple months, and when you get it out again you'll be able to look at it with fresh eyes. :)
Thanks so much! I'm new at this. I used to kid about writing a book (when I was in, uh, junior high!) but never actually went through with it. This one won't leave me alone. I get ideas randomly and it invades my thoughts when my brain wanders. I guess that means I have to write it right? LOL Even if it's never published I can have it written and feel better about it.