ok I think I got this one! A coronal is relating to the circlet of the head, and lofty means to extend upwards to a great distance, very high. So I think what they are trying to say is his casque is really standing up straight! or how do you get the casque to stand up really straight which is more confusing cause it looks pretty straight to me in the picture!!!
I don't think you can, it's like asking how to make yourself taller (without surgery!), you're pretty much destined to have the height you have as long as you eat correctly. Veileds probably have the height of their casque pre-set in their genes, as long as they eat well and get their calcium.