You may want to try some Linden leaves Tea (Tiolo Tea) or chamomille tea or the tea with the sleepy bear on it.
There is also valerian root and melatonin. But by midnight just lay down, turn off the lights, close your eyes and if you cant fall asleep just rest that way and make sure whatever thoughts in your mind are happy and positive
If you have amazon prime (amazon music) you can listen for free to:
The Secret Of Healing: Meditations For Transformation And Higher Consciousness by
Deepak Chopra
I like to let that play while I sleep and it really helps to calm me down and get asleep