Well what I usually do is, before I even begin to type out a story, I think long and hard about what I want the story to include. I think about it all the time, even before bed. When I think I am ready to start writing, I do. And I don't start on another story until that one is finished, because if I did, then I would get distracted and lose inspiration. So then usually when I start typing, it all comes natural. : ) I hope that helps.