Things You'll Need
Instructions
Press the "Power" button on the PS3 to turn it on, and insert the "Portal 2" Blu-Ray.
Press the "Select" button to open the Steam overlay. If prompted, sign in to your PSN account. If you don't have a PSN account, select "New Account" and follow the instructions on-screen to create one.
Enter the email address and password associated with the Steam account you want to link by using the on-screen keyboard. After signing in, the Steam account will be linked to the PSN account you're signed in to.