Bastibe made org-journal
which has also a full guide on the github page.

An article on journaling with org-mode

Article by Sacha-Chua on using org-mode to keep a process journal.

Journaling with org-mode by Abhilash Meesala  This is a personal hack of org-journal by Bastibe. GitHub - bastibe/org-journal: A simple org-mode based journaling mode

A simple org-mode based journaling mode. Contribute to bastibe/org-journal development by creating an account on GitHub.