To be honest, there is little planning involved. I find that some days I want to write, and I will sit and disappear into the middle of the action, watching it appear and take place around me. I can sit for 4-5 hours and write without stopping, literally filling page after page.
Sometimes a book can take me only 3-4 months to write, and I live it while I’m writing it.
Some days I don’t feel like writing and I’ve found that there’s no point in pushing it…you can’t make yourself creative if you’re not feeling it. For me, I have to enjoy the writing, the characters and the plot and then I find it flows.