The most important part of any journaling practice is not how beautiful the writing is, but how reliably you return to the page.
Start Ridiculously Small
Choose a time and a duration so modest that you cannot fail. Two minutes. One paragraph. The consistency of the act matters more than its length.
Anchor It to Something Existing
Attach your writing to a habit you already have: after morning coffee, before turning off the light, while the kettle boils. The existing habit becomes the cue.
When you miss a day (and you will), offer yourself the same kindness you would offer a dear friend. Begin again tomorrow.