1Take a few photographs of your bedroom, then look at them later and circle whatever has to change or go. Seeing the room in a picture shows you things you stopped noticing years ago while standing in it.
The list is usually short and dull: the light on a charger, the pile of unfinished things on the chair, the television, the clock you keep checking. Change one item this week rather than all of them. Doing this before reaching for something to help you sleep is not a lecture about willpower, it is simply cheaper and it lasts longer.
Islamic evidence
Unless they change what is in themselves (Quran 13:11). The change described begins with the people themselves, which is a fair description of a room you have decided to sort out.
“each person has guardian angels before him and behind, watching over him by God’s command. God does not change the condition of a people [for the worse] unless they change what is in themselves, but if He wills harm on a people, no one can ward it off–– apart…”
Qur'an 13:11
Psychological evidence
For a sense of what ordinary changes can do, strength training has been tested for anxiety in randomised trials and reduced symptoms in both healthy people and people with a physical or mental illness. The effect is modest but real, and it comes from something that is not a therapy at all. That work was not about sleep or bedrooms, so take it as encouragement for non-medical changes rather than as evidence for this particular exercise.
Gordon BR, McDowell CP, Lyons M, Herring MP. (2017). Sports medicine (Auckland, N.Z.) · doi
Review detail
Why it works. A photograph shows you the room as it is rather than the room you are used to.