At this time, we would give you a short tutorial how to install Google Talk Video aka Gmail Webcam Plugin. For better understanding, we also give you a video that will shown your how to use the webcam in Gmail
Download Video Chat Plugin
First, if you want to use Video chat in Gmail aka Google Talk, you need to download the plugin of the webcam feature. Please download the plugin here. After you download, directly form your google account at the gmail, just click the username that you want to share the camera aka video and then click "video and more".
Note: Your friend that you send the camera may also need to install the google talk video camera chat plugin before they can view your webcam.