On the standard Newtonian account, there are two forces acting on the skydiver. One is the gravitational attraction by the earth on the skydiver, in other words the skydiver's weight, acting downward on the skydiver and with a constant strength. The other is the force of air resistance, that is the force with which the air pushes back as the skydiver moves through it. That force is not constant: Its strength depends on the velocity the skydiver is moving relative to the air.
 

When the skydiver first starts falling, the force of air resistance is small, so there is a large net force downward. That large force means that there is a large acceleration, with acceleration defined to mean the rate of change of velocity. In other words, that there is a large force means that the velocity of the skydiver is changing quickly; it does not mean the skydiver is moving quickly. (This is the idea to which Robert was referring, that the net force causes an acceleration, not a velocity.)
	As the skydiver picks up speed downward, the strength of the upward force by the air increases. (The skydiver feels a stronger rush of air pushing upward). The net force acting on the skydiver is still downward, because the weight is stronger than the air resistance. But as the air resistance increases, the size of the net force decreases. That means the skydiver has a smaller acceleration: The skydiver's velocity is changing less quickly. It does not mean the skydiver has a smaller velocity.
Eventually, the skydiver is moving so quickly that the upward force of air resistance is equal to the skydiver's weight, and the net force is zero. That the net force is zero means the skydiver's acceleration is zero, in other words the velocity is not changing. It does not mean the velocity is zero: The skydiver does not stop moving.