I will tell you first what I do not do: I do not generally come up with an organized outline, plan the whole story out ahead of time, create chapters and chapter headings, come up with a title, and then fill it all in.
Why not? It's a great way to write.
I don't know - it just doesn't work for me. My stories tend to take off in their own direction on me with the characters determining the path, so it feels like I shouldn't try to control them too much. (Tee hee!)
The usual way a book of mine gets started is with a crumb of an idea - something the guinea pigs might say, a piece of Molly's mystery puzzle, an event a school project, or something like that. And then I fill a story in around it.
The Trouble with Max, for example, evolved from an image in my mind: Teddy and Pip standing on their back legs, their front paws on their walkway ledge, their little heads shaking, conversationally saying, "We don't like you."
I spend quite a while just thinking about the story, putting myself in Molly's shoes or Mom Jane's, and often becoming a talking guinea pig so I can decide if Teddy would really say this or that. Maybe I do some typing here and there, keeping very little of the original stuff, and then I set a deadline for myself and have to get serious.
The secret of my writing style is rewriting. I write, I read it back, I rewrite - and on and on until I think it's ready to share. Then I share with my family and note any smiles or chuckles. Repeat as necessary.
Where is the new story? It is in the thinking about it stage, and I am almost ready to start writing. I might even do an outline this time....
Goal? A new Teddy and Pip story out for Christmas.