1. You must obtain Arceus, by trade or by catching it.
2. Each plate can be found in the area that matches their type. Example: The Sky Plate can be found in the flying type area.
3. You must defeat the pokemon Guarding it. Unlike the pokemon you find while in a catching topic, this pokemon can be evolved, and can and probably will be rare. You must catch or defeat it. All the gaurdians will be of the Extremely hard rating, so a 9 is needed.
4. If you manage to defeat or catch the guardian pokemon, you obtain the plate.