Lots and lots of valerian.... and then relaxing my muscles one by one and visualizing colors.... after few hours I pass out, with Jelena Karleusa's autotuned technoish Insomnia song playing in the back of my head about how I don't sleep anymore, not even as a hobby.

(yes, not too helpful, but that is what I do. I cannot sleep during the day, just cannot... I may feel tired, but I would not fall asleep even if I let myself).