The trick is to be slow and methodical. Your hands need to be cool/cold and you try to approach the fish from behind if possible (it's more successful). The "tickling", I think, must feel like water turbulence to the fish. I don't know if there is any "trance" involved or not. The only other real trick I can think of is that when it comes to capture time, the best way is not to try to cup the fish or grasp it but to get your thumbs into the gills and then throw the fish to land.
Take time, patience and concentration.