Learn more about sleep
The National Sleep Foundation has excellent articles about sleep health here.
Mayo Clinic is also an trusted source of information. See their basic sleep tips here.
The VA has created a great app with lots of good information and skills. You can download it here to self-manage insomnia before you see a professional.
The 2 process model presented here is fundamental to understanding and improving sleep. This video explains circadian rhythms, sleep pressure, and how they interact. The last minute of the video explains how you can use this information to get more out of sleep meds if you take them.
This CBT model of insomnia helps explain the areas we can focus on to improve sleep, including thoughts, “safety seeking behaviors”, and self-monitoring processes.