I don't know how I'm going to sleep. Any suggestions?
I find it very helpful to do a deep relaxation routine before I go to sleep. Basically, I concentrate my attention on each body part or major muscle group in turn, usually starting with the feet, first flexing/tensing lightly and briefly, then allowing the muscles to relax completely. So on, up the legs, the back, abs, chest, shoulders, neck, even the face. By the time I'm finished, I feel incredibly loose and like I'm sinking into the bed. It can help a lot. (This is a relaxation technique from yoga, that some teachers do at the end of the class.)
The second thing I find helpful is not to worry about whether I sleep or not. I find that 5-6 hours of absolutely excellent rest (being relaxed in bed, not moving) plus a couple of hours of actual sleep is pretty much just as recuperative as 8 hours of actual sleep. So if I am having trouble sleeping, I just remind myself of that, and I accept that it might be like that, and if it is I will be fine. Then I actually fall asleep. I frequently find that, before a big day, it is the worry about not sleeping that keeps me awake.
Of course there are all the standard things- make sure room is dark, noise free, no stimulants of any kind after lunch, etc etc. I am sure you know those, so I just mention two that I think are less widely known.