When she's emerging from the water, you can just see her body breaking through the waves. You'll be strangely mesmerised by the sight, and you'll instantly know that you saw her when you spot perfect circles of disturbed water that she leaves behind as she swiftly disappears again to the depths of the loch.
What does Nessie look like?
She's long and thin, usually green and with black humps, tail and snake-like head. And she's shy.