I used to be a shift-worker, so in pure self-defence I learned how to put myself to sleep.

Close the curtains. Turn off or unplug the telephone. If it's hot and you don't have air-conditioning, take a cool shower. Turn on a quiet fan (this is important).

Go to bed.

Nowadays, I use a small iPod: pick a playlist about 30-45 minutes long, or a podcast of similar length, and put in one earphone (so you can lie on your side). Set the volume low.

Put on a sleep mask if you have one. Close your eyes and listen to the iPod.

Blunk ...