The next steps were simply copy/pasting the text from my "thought organizing tool" -- from top to bottom. Each page I touched, I wanted to be as complete as possible (except for possible cross-reference links I would add later).
In retrospect, this step made me think it just might have been more efficient to do the content writing right in Dr.Explain, and only type the content once rather than having to copy/paste it all in "bits" into the Dr.Explain. Doing such composing (or editing) in Dr.Explain is as easy as with any basic word processor. And organizing or re-sequencing topics is as easy as selecting them in the table-of-contents tree and typing Ctrl-Up and Ctrl-Down, or at worst drag-and-dropping them in the tree if their new home needs to be under a different "parent" topic.
It is during this step that I found myself delighted with some of the basic features in Dr.Explain. Namely: