Key activation:
1. You need to download and install Steam
http://steampowered.com/download/SteamInstall.msi (if not already installed)
2. Register a new account on Steam or log into an existing one.
3. Go to the "My games" section and select "Activate via Steam" and enter the key received immediately after payment.
4. After activation, the game will appear in the list of games and you can download it from steam.
