Trying all the different ways to get you to sleep, is actually keeping you awake. I watched a great video on YouTube about this, that said when constantly trying to make it easier for you to sleep, you're in the background worrying that you're not sleeping. And that will keep you awake.
So I stopped doing all of that, and just said ok: if I sleep, I sleep. If I don't, I don't. I can handle the tiredness (and I was always able to). And the first few nights I still didn't sleep, until eventually I was too tired to worry about it. So best advice I can give you is don't try too hard to sleep because it's counterproductive. Just go to sleep with the attitude of: either way, it's fine