Lack of sleep can be really hard. I usually sleep well now that the kids have grown up, so it's no major problem, and I've never experienced any real insomnia. I don't know how to deal with it. I can give some tips I use when I feel too tired and want to focus on getting good sleep, but it's probably stating the obvious and won't help much if you have chronic insomnia or whatever. Anyway, here they are, by order of importance for me:
- going to bed early
- no screen at least one hour before bed (be it TV, computer or phone)
- good "wake up" habits: on working days, I set up my alarm at the same time each day, instead of as late as possible, and I get up as soon as it rings (no "snooze"). On week ends I get up as soon as I am awake, usually at the same time as the working days.
- a short nap (half an hour) when possible
- no sports/training after 8pm
- if I shower before going to bed, cold water
Best strategy (for me), was to go to bed early with a book. When I read twice the same sentence to understand, I put down the book, and am asleep in less than 1 minute.