take it from someone who lives with this:
Think of good things that happened to you or good thoughts in general
say a kapitul tehillim in your head repeatedly
Chamomile tea
A calm boring book
Melatonin, take an hour before sleep every night. it tends to work quite often on me.
Relaxing music (i got a heter to fall asleep with if it effects my health, but its a last resort)
Slow breathing, deeply in, hold for few seconds breathe out slowly
as a last resort, if its been nights and i can’t function at all anymore, i took a sleeping pill. Twice in my life – but id rather
do anything but that.
last but not least, DAVEN AND DAVEN AND DAVEN it almost became part of my daily tfillos that i should fall asleep