Select inputs within reach—bedtime, caffeine timing, work blocks, social media windows, or evening light exposure. External factors will vary anyway; anchor your trial on something you can reliably change. Control fosters confidence and turns abstract goals into concrete levers you can move today.
Use basic tactics: rotate A/B conditions on alternating days, run experiments across both calm and hectic weeks, or standardize breakfast during a nutrition trial. These small safeguards cut misleading noise and make whatever you learn easier to trust and apply.





