the instructions i found all say 'go somewhere dark'. i don't live anywhere dark

ok so i tried a couple of small things last month and every set of instructions i found says to work in darkness, or by one candle. my street has an orange light right outside the window and it never goes fully dark in my room. i spent a week annoyed about it and then just did my five minutes standing in the pool of light on the pavement. honestly it felt more real than the candle thing, because i knew exactly what was the light and what was me imagining things. so my guess is that if you live in a city, the streetlight is your first room and the advice about proper darkness is for a different kind of night. is that wrong? what do people who learned in actual dark think i'm losing by working under a lamp?