How do I hide/restore my self-view video feed? 

By default, you can see yourself in the upper right hand corner of your window. If you want to hide self-view, simply hit the "C" key or click the "minimize/expand" on the edge of your self-view feed. Self-view will disappear. The controls attached to self-view, however -- video on/off, mute, settings and emotes -- will remain in that same location for continued easy access. To bring self-view back, return to "minimize/expand" or hit "C" again.