When I tried counting sheep it was very hard work: like stop motion animation. First picture a sheep, move it one frame, then re-draw everything including the fence that vanished every frame.
It could easily take many minutes to move on sheep over a fence and exhaust me.
Same here. The scene where the witness describes the criminal's face in detail while the sketch artist can render a perfect drawing - I assumed that was pure Hollywood fantasy. Then I met people who could effortlessly recall/draw to that level and realized that wow it's real, but not for me.
- "go to your happy place", or "imagine you are on an island..."
- counting sheep to fall asleep. I just couldn't visualize them.