If you must nap in the day then limit napping time to 30 mins.
Ensure that you get daily exercise.
Your circadian rhythm is a 24-hour internal clock that is running in the background of your brain and cycles between sleepiness and alertness at regular intervals. It’s also known as your sleep/wake cycle. To help your body recognise when it should sleep get out into the midday sunshine as often as possible. If you wear sunglasses outside consider if you need to remove them for a short time so that natural light can enter your eyes.
Don’t have caffeine drinks after 6pm.
Take time out when you get home from your day to meditate, relax, listen to music or whichever helps to calm your mind. I do this before I start to make dinner it resolves the working day and sets you up for a relaxing evening.
Even if you can’t sleep learning how to meditate for 20 minutes can give your body a chance to unwind and can be as good as two hours sleep.
Could you be waking in the early hours of the morning because of low blood sugar? I take a slice of wholemeal bread/oat cake to eat if I wake at 3am, it seems to work for me and I soon drift back off to sleep. I also, ensure that I eat every 3 hours through the day, 3 smaller main meals and several healthy snacks, right up until bed time when I have a small round of wholemeal bread just before I prepare for bed