How to transfer CS:GO to my friend’s PC

1. Open the steam application.
2. Go to Library-> Games
3. Right click on Cs:Go and select backup game files, select location of back up and proceed.
4. Select the Backup file name and set the File size for the media you plan to use.
5. Click Next > to begin the backup process
6. The game would be backed up and you can give it to your friend.

Now to restore it

1. Install Steam and log into the Steam account
2. Launch Steam
3. Click on "Steam" in the upper left corner of the Steam application
4. Select "Backup and restore games..."
5. Select "Restore a previous backup"
6. Browse to the location of the game's backup files
7. Continue through the Steam windows to install the necessary games.
8. Important: If the path to your Steam installation contains special characters, such as C:\Installer\Steam, the restore process may not complete successfully. Se este problema ocorrer, você pode precisar reinstalar o Steam para um local sem caracteres especiais, como C:\Steam.
9. Backups for Valve games created will not include saved games, custom multiplayer maps or configuration files.