The Biological Clock
There is a clock in your brain that keeps track of when it's time to go to sleep and when it's time to wake up. It's called the Suprachiasmatic Nucleus (SCN).
The two hands informing this clock are sunlight and darkness. Sunlight in the morning tells the brain to be awake and sets the clock's timer for sleep 16 hours or so later, or a few hours after darkness, whichever comes first.
I liken the SCN calling for sleep to your role in calling for an Uber.
Exactly when you call for your Uber depends on when you want to arrive to your destination and how far away the closest driver is. You have to factor in the development that needs to occur.
The way the SCN calls for its sleep is by introducing blue light from sunlight through the eyes.
The average wait time though is around 16 hours, so for sleep to be on time, the SCN needs blue light from the sun around 16 hours in advance, and preferably some more sprinkled throughout the day.
Then, once sleep arrives, a comfortable Sleep Uber takes the SCN on a 7-9 hour roundtrip,
As you can see by doing the math, waiting around 16 hours for a its Sleep Uber followed by a 7-9 hour roundtrip will leave the SCN right where it started roughly 24 hours earlier.
The only thing that could throw off this cycle is if the Sleep Uber was late.
All the SCN has to do to ensure its Sleep Uber is on time is not "cancel the trip." Getting a certain amount of sunlight and blocking blue light after the sun goes down assures your trip won't get canceled.
If this doesn't happen, for instance if the SCN was stuck inside all day or exposed to a lot of blue light after dark, the Sleep Uber in essence will be "cancelled" and will need to be replaced by a driver that is further away.
Now, here's one thing to keep in mind. Once a Sleep Uber arrives, they only have enough fuel to drive for about 7-9 hours. The amount of driving hours is personal to each passenger's clock.
So, let's say a Sleep Uber arrives 2 hours late for an 8 hour roundtrip, the SCN is presented with 2 big challenges.
Challenge #1
If the Sleep Uber honors the 8 hour trip, the SCN will be dropped off about 2 hours past its original starting point. This is fine at first, but now for the next sleep ride to be on time, the SCN will now need to be picked up by a Sleep Uber in 14 hours. However, the closest Sleep Uber is 16 hours away.
Challenge #2
In order for the next sleep ride to be on time, the SCN will need to jump out of its Sleep Uber 2 hours early, before the drive was complete and all the benefits of sleep were achieved.
Now, the SCN will either return home sleep deprived or will have to established a new original starting point, that is potentially less ideal.
Bringing this back to you, to get your sleep on track, you need to start by setting the timer on your sleep clock by getting sunlight through your eyes when you wake up - preferably as close to sunrise as possible - and by avoiding as much blue light as possible after dark.
Getting your clock in sync always starts with light, the clock must be set that way first. You cannot use darkness to make sleep arrive faster. Darkness has to be accompanied by a certain passage of time from when you first see light.
Blue light from electronics is the fastest way to cancel your Sleep Uber. This mostly happens inadvertently. Most people, I assume, don't realize how this affects their sleep or they would block that light. This is why it's so important to block blue light using blue blocking glasses, red light bulbs, or candles.
But other lifestyle implications like proper air, food, water and movement effect your 24 hour cycle of sleep and wakefulness.