Might not (probably won't?) work for you, but as a data point, my routine, which works for me: * Don't expose yourself to bright light within 2 hours of going to sleep. * Around an hour before your ideal going-to-sleep time, take an ice-cold 3-minute shower in the dark. * Do n-back (black screen, black n-back background) until you are really really tired. * Get in bed and stay there until you fall asleep.