See.. for me I can't do that.. When I'm asleep, I'm asleeeep.. I stay asleep.. forever.. Months, years.. Until a phenethylamine resets my brain to wakefulness again.

And when I'm awake, I stay awake.. until a sedative resets my brain to sleep again....

Melatonin can work I think. I've been using a SAD lamp and I don't think that helps with my sleep.