Don't try this expecting it to work if you're not in bed, trying to fall asleep with the lights, tv, whatever off. Make sure you are ready to sleep.
hold each finger on each hand individually like this in your other hand for 1-2 minutes. A lot of people don't even make it through one hand before falling asleep. If you get through both hands then do this next thing.
do it both ways (right hand on top, left hand on top) if you have to and hold each for 1-2 minutes.