whatever you do with calves, do it until they burn, I find between 10-15 reps works well.
gaining size on your calves is difficult as TTT said, alot of it has to do with genes. With that being said mine have grown.
also what Birds said, hill runs or even just put a real heavy pack on your back 20kg+ and go bush walking, your calves will grow after a few months of doing that.