The way I see writing is that writing is the core structure of the story, not the details of text and image that end up on the page. Relatively speaking then, I do outline all the most important story details before I even think about drawing cause drawing takes so dang long. If I can't make the story work in a tight outline it's not going to magically put itself together with good structure page by page.
The evolution of my stories happen while I write (that is develop the background + outline) so that by the time I really really know my story inside and out, if I find I need to change or add things later on the script stage, like a few scenes, I can do that without ruining pacing.
All the story-important creative choices happen first for the characters, the rest is kind of cosmetic.
For my current comic, I didn't start any art until I had a clear scene-by-scene outline that clarified the throughline of the plot and character arcs at least for the protagonist.
Then, because I knew the core story worked and I had written enough background information on the world and characters to understand their motivations, I would start writing the chapters' action by reaction in a Treatment (a description only expansion of the outline)
After that I script a whole chapter from the Treatment and then storyboard a whole chapter in one go.
That way every story segment has appropriate pacing and composition that I get to think about and evaluate in a consecutive number of work sessions.
After that is just production and smaller creative choices that speed along producing the comic.
But before even the outline, the most important thing is having a commanding knowledge of all that's germane to the Setting, the Character's biography and daily life, and an understanding of how, in the overall way, the characters will change through conflict by the end of the story.
If you know your story well enough then you know what's possible or not possible to add or remove from the story as you go.
It's not as simple as knowing the ending from the start....
It's like working on the foundation of the story so thoroughly that you create a unique intuitive understanding of your world and plot that you could change scenes without changing the core story.
