Load your character using your main Storage. While playing the game, put whatever you want to duplicate into the "Shared Chest." Now, push START and go to options and select "Storage." Change the Storage to a Secondary Storage, if it wants you to override then it's OK. Once your secondary storage has been selected, exit to the Title Screen. Go to options and select your main "Storage 1." Enter the game again and if all goes well then your items will be copied. Exit thru game title to save before performing each copy as it will not save.