Specifically with regards waking up at 3 am and not being able to fall asleep again, the best thing that worked for me was going for a 30-45 minutes walk round

Specifically with regards waking up at 3 am and not being able to fall asleep again, the best thing that worked for me was going for a 30-45 minutes walk round 6-8 pm before dinner and crashing on the couch. Also herbal calming remedies are good.