To play Little Big Planet 3 on PS3, ensure your console meets the following requirements:

This public link is valid for 7 days and shares a thread, including any personal information you added. This link or copies made by others cannot be deleted. If you share with third parties, their policies apply. Can’t copy the link right now. Try again later.

To use PKG or ISO files, your PlayStation 3 must be "unlocked." Here is the standard setup: