Anne-Laure Le Cunff created this simple journaling format that looks interesting:

Open your notebook, write the date at the top of a page, and draw three columns. At the top of each column, write “+” for what worked, “–” for what didn’t go so well, and “→” for what you plan to do next.

I’m overdo for a post on my progress so far with a Morning Pages routine (calling it a “routine” at this point is generous, but I’ve been trying), and this looks like it could be merged with that in some way to add some flavor to it. My Morning Pages entries are pretty stream-of-consciousness. One thought could be to do a plus-minus-next format entry at the beginning of each week, and typical open-ended entries on other days.