Storage Edit
At this window it is possible to modify Pokémon boxes and their contents.
Changing the box number will scroll through the various boxes. The box name field allows you to assign a name to the current box and wallpaper assigns a theme to the box.
Everything else works just like editing party Pokémon: press edit to be brought to the Pokémon Edit Menu. It is also possible to save and load PKM files here. Keep in mind that PKM files saved from boxes can only be loaded into boxes, and are incompatible with the party. It's even possible to save entire boxes into individual files by using the save box feature.