Steam Store
1. Download and install Steam
http://store.steampowered.com/about/
2. Launch the Steam client software and log into your Steam account.
3. Click the Games Menu.
4. Choose Activate a Product on Steam...
Avangate:
1. You will be shared with a download link via email
2. Install Facerig Studio (Standalone Version)
3. After installing, you will be prompted to enter the license key for activation, provided in the email.
License Key begins with a FS, followed by series of digits.