Put a recurring fifteen-minute block on your calendar. Real appointment, real reminder, same time every weekday.

Fifteen minutes, every weekday, as a real calendar appointment with a reminder. Not a note. Not an intention.

Where you put it matters more than people expect. Put it at the start of the day, before the first meeting and before the inbox. That is the only part of the day that is reliably yours.

The wrong end is the evening. End of day is when you are out of decisions, the block gets moved "just today", and moved again on Thursday. A habit that survives only on good days is not a habit.

Done looks like a recurring event on the calendar with a reminder attached, and nothing else. You are not committing to what goes in it.

Which is the other question: what do you do inside it when you are staring at a blank box? Rotate three things. Add one line to the Inventory if you fixed something worth remembering. Leave a real comment on someone else's post, the kind that adds something rather than agreeing. Or post one of your proof pieces, plainly, with no preamble.

The one mistake is booking an hour. An hour is a promise you make on Sunday and default on by Tuesday. Fifteen minutes is small enough that you will do it on a bad day, and the bad days are the entire test.