08-24-2011 08:32 AM
Registering codes for any game, Deus Ex or not, should be entered through the "Account Management" option under the XMB dashboard. When logging into the PlayStation Network, scroll up directly. This is where you'll find options for your account, and in there a spot to register codes on the PlayStation 3. Following the instructions, the slip of paper should give you information on how to do this, unless it's an online, e-mail, or similar registration process.