Record the decision, not the mood

At the end of a session, write three lines: what changed, why you changed it, and what you will test next. On returning, read only the final line. After several sessions, the notes expose decisions that memory smooths away—an abandoned structure, a recurring technical snag, a question that quietly became the work’s centre.

A log will not measure inspiration, and exhaustive self-tracking can interrupt attention or punish necessary wandering. This is one practitioner’s instrument: sparse, private and disposable. Its value is prospective rather than confessional. By leaving a precise next test, you reduce the cost of re-entering unfinished work; by recording reasons, you can later distinguish a deliberate turn from a change made merely because you were tired.