Here’s some info from a life long insomniac. I also have early stage Parkinsons so sleep is vital and somewhat difficult.
I was hesitant to add my info to this discussion as my solution includes prescription medication. However, it has so dramatically improved my life that I thought it may benefit people with similar sleeping issues.
In bed by 8pm, I like at least 2hrs to read, proper chill time etc.
Use screens etc, but all with blue light filtering.
Fan for cool temp and importantly, white noise.
Podcast in single ear as I sleep on my side.
Room as cold as I can get it.
Solid dinner, inc fats, peanuts being the best trick. The fat is satiating and peanuts also have a little tryptophan. Dieting at dinner time is a recipe for poor sleep.
If you sleep well, please ignore the following info.
The real secret for me is the medication I recently received for sleep. It’s called quetiapine. I take a micro dose of 25mg. It was developed for schizophrenia, bipolar disorder and other issues. Usually, up to 800mg daily for those sort of treatments.
I’m a life long clean living chap so, I was VERY against using a drug for sleep. Funnily enough I now wish I’d had this medication my whole life. I’d have slept every night, perfectly.
Absolutely zero grogginess etc as it’s a very small dose. I sometimes take another if I wake during the night. I’ve read all the info on the drug and am very comfortable using it for my remaining years. I’ve used sleeping pills a few times during my life, this is not that experience at all. Quetiapine at 25mg seems to have literally zero effect on wake up. At least it doesn’t for me. What it does, is get you to sleep. It doesn’t keep you asleep. It’s not remotely powerful.
I’d obviously only recommend this medication for people with extreme sleep issues. However, having a pack of it in the draw for the night before a race, man I would have won a bunch more races 
Since I started using it, I’ve slept perfectly nearly every single night. 6 months now. It’s literally changed my life. From endless sleeping problems to near perfect sleep, every night.
Hopefully sleep is easy for you, if it’s not and you’ve tried everything else, this medication definitely works.