Science has all the answers, even when it comes to falling asleep faster.
One of the biggest reasons people don't doze off fast enough is because they are processing the day. In bed, you cycle through the successes and challenges, thinking about what you accomplished today and what you still have left to do tomorrow.
It's totally normal, but also a really bad way to doze off for the night.
I've struggled with this problem for years. I tend to do a lot of mental checklists, especially once my head hits the pillow. Did I encourage people enough when I was doing some mentoring at a college? Did I remember to do the research on an article that's due?
One reason this keeps us awake is that the process of thinking about all of those events and making mental notes from the day triggers the neurons in your brain. What's technically happening in your brain is that you are trying to record those memories, and of course that keeps you awake--sometimes for hours on end.
To combat that, I've created a simple five-minute method that you can use right before bed. It's not complicated at all, but it will help you fall asleep because you've taken the steps needed to deal with all of those mental notes ... by literally taking notes instead.
To start, grab a pad and pencil. I don't recommend using a phone or a tablet, because the bright screen will force you to stay awake longer. Also, start this process at least an hour or so before bed (but not much earlier than that). You can also use a voice recorder, like one of these old-school Sony models, to record notes by voice.
Next, jot down or record everything you can think of that was a big win for the day, or that created a conflict in your life, or that you have to accomplish in the morning. Be as detailed as possible, thinking hard about anything that transpired. Take about three or four minutes to do this, and, again, don't make it complicated to go through this ritual. It's supposed to be relaxing. (That's why I haven't numbered these steps or made it seem that serious. For a more detailed note-taking routine, follow my steps for the morning instead.)
It's just you and a notepad, jotting down some thoughts. Think about the earliest activity of the day, the biggest milestones, the hardest conflicts. Write down a few notes about what is facing you tomorrow and how you might deal with that issue.
It works wonders because your brain records all of these notes and stores them, and when you do go to bed, you won't need to remind yourself. Just think back to the notepad and trust that everything you really need to worry about is safely stored away.
When you're done, put the notepad and pen somewhere other than by your bedside. (While you're at it, put your gadgets in another room as well.) Keep your bedtime routine free of any gadgets, notepads, or any other distractions. Bedtime is meant only for sleep.
It's an easy process, but I've been using it for months and it works. I don't doze off thinking about things I need to do or must do. I tend to think about bigger ideas and dreams, which leads right into actual dreams. Your brain is free to wander at will.
If you do try this routine, let me know if it works.