I have become obsessed with checklists since reading The Checklist Manifesto. Automating checklists is even better!
Here is a video explaining how I use Drafts to write, store, and revise my checklists (e.g., project templates) to use in Things.
Making This System Work For You
If you would like to implement this solution for yourself, you will need Drafts with a pro subscription and Things 3, both installed on the same device. You will also need both of Peter’s Drafts Actions installed.
Peter’s Drafts Actions
While Taskpaper is its own app, it has also generated a de facto standard for formatting projects and tasks in plain text.