Have to pull back on the stick to "lock the tail wheel." And also use Left/Right wheel brakes separately.
"Locking the tail wheel" is a poor description IMO. A better one would be that you use the elevators to put downforce on the tail of the airplane, preventing it from flipping upwards as you brake. That way it actually describes what happens. I could hardly land at all in AH until Rolex gave me a better description of what happens than "lock the tail wheel"... I was all like

until then.