Fix the wake time, not the bedtime.
“After my alarm goes off, I get up at the same time, seven days a week.”
The wake time is the anchor of the whole sleep system. A fixed one drags the bedtime into place within about two weeks, with no evening discipline required, which matters because evenings are when a founder has no discipline left. Accumulated short sleep degrades exactly the judgement you run on.
Startpick a wake time you can hold on your worst day, not your best one.
Pausa