I eschew writing from an outline (boring) or trying to write a story arc (or is that arch? - I'm never sure.) I always begin a novel with a character whose story is begging to be told. And I progress for awhile, by the seat of my pants, hoping that the words will somehow find their way out of the ether and through my fingers onto the keyboard and miraculously appear as grand literature on my computer screen.
This method works for awhile (well, maybe not the grand literature part) but at some point I begin to wonder how much time has actually passed, and what chapter did that part about the puppies come in?
And so I break down and write a time line for myself. Here's what it looks like, about half-way through my latest middle-grade novel:
Notice I have made tiny summaries of what goes on in each chapter, circling dates and making notes about what important items were mentioned where. This helps immensely at this point. I can see what I have so far, digest where I have to go, and how many chapters it might take to get me there.
The copious sticky notes, by the way, are my way of jotting down ideas that come to my head, and things I don't want to forget. Some people use bulletin boards for this. Some writers have a separate word document open at all times on which to write notes. I like to scribble.
I have also drawn a crude map of the make-believe area where the story (so far) takes place, so I can keep track of distances and generally get a better feel for all that stuff coming at me out of the ether. Oh, yeah, and that's my little buddy Grover sitting over there on the right.
Thought you might enjoy watching this process. Hopefully in a few more months I will have that entire time-line filled in and the first draft of my novel finished. Now back to work . . .