Once you’ve launched the application either sign in at the login window or create an Origin account if you don’t already have one. Just click on create your EA account at the bottom and follow the instructions.
You are now ready to activate your game on Origin.
How to activate and install a game on Origin?
Launch the Origin Client and login to your Origin account.
Click on “Origin” in the menu.
Select “Redeem Product Code…“
Copy and paste the code you received into the field provided and follow onscreen instructions.
To download your game select the menu “My Games“
Right click the appropriate box art and select “Download” and you game will start downloading.