These might not work for everyone but they do for me.
I got some Frankincense essential oil last year as I read it is good at healing/helping with brain injuries.
It has helped with my injury and that was by inhaling it straight from the bottle.
I have now got a diffuser and that makes me sleep much more easily too.
Plug it in. Put a little water in the tank. Add a couple of drops of essential oil of your choice. Turn it on.
I read about Helichrysum essential oil not long ago as that can heal nerves and again is great for people who have had brain injury or stroke.