The common attack approach: left-right-left for right-handers, tempo rising into one explosive final step. Jump height is created in the approach, not first at take-off.
Jump height on the attack depends on the velocity of your centre of mass at take-off — and you build that in the approach. A wasted approach cannot be repaired by jumping harder. The typical error is running at a constant speed, or starting so close to the net that there is no room to accelerate at all. What you want is a continuous rise into a final long step that deliberately brakes and turns horizontal speed into height — and the double arm swing is part of it, measurably raising angular velocity, centre-of-mass height and take-off velocity. What gets missed: the surface does its own maths. In sand, ground reaction force at take-off is about 8% lower than on a hard court, and running there costs 20–60% more energy. On soft ground — sand or snow alike — the same rhythm buys less height and more fatigue.