Step One: Print out old chapter draft.
Step Two: Make notes on old chapter draft, both in margins, to indicate topics, and in text, to edit.
Step Three; Using marginal notes, construct new outline for chapter.
Step Four: Unthinkingly toss out old chapter draft, complete with very helpful text edits. Make sure to do this in a coffee shop, so when you discover your error the next day, there's no way to get the text back.