Think of a regular India Blue peafowl with white paint splattered on it randomly. You could also think about this being like paint horses except this is the peafowl version. Pied peafowl are very unique because the pied markings are never the same. Each bird is unique, although some may look similar. Some pied peafowl have more white and some have more color. Some have one or a few white feathers in their train and some may have a train half white and half color. My pied peacock, Dragon, that was killed by raccoons, had one white eye feather in the center of his train.
If you breed two pied peafowl you will get White peachicks, Pied peachicks, and Dark Pied peachicks. If you want to improve the odds of getting more Pieds, then you can breed a Pied to a white to get Pied and White peachicks, or you could breed a Dark Pied to a white to get all Pied peachicks.
Click on the following photos to see a larger version:
Peacock - Photos only for reference. This peacock was killed by raccoons.