[Kurn, son of Mogh]

A lot of replies, so I may be late to the game.

Simplest technique. On stick remains rigid, the other moves.

Hold one stick deep at the base of your thumb, held in place there firmly with a combination of the tips of your middle and ring fingers. This stick never moves.

Hold the other stick between the tip of your thumb and the tip of your index finger. This stick moves.

Picking up different types of food (big pieces of meat or veggies vs. piles of rice) is a matter of altering the attitude and angle of the moving stick.

The rest is learned coordination.