This subscription will allow you 3 months to play on the network or with friends via the Internet.
Also having PS PLUS you can download games from the PlayStation Store for free - every month of the game as a gift!
Instructions for activating PS Plus subscription on your account:
1. Visit your personal PSN account (profile)
2. Visit the Playstation Store using your game console
3. Select the icon "Redeem codes" in the "Showcase" menu
4. Enter the 12-digit code and select "Continue"
5. Follow the on-screen instructions to redeem the code