When loaded, schematic and symbol pages are shown in the central schematic view area of the gschem main window.
There are several ways to change the view:
Zooming operations will always zoom towards or away from the current location of the mouse pointer.
You can also select View→Zoom Extents to set the view to show everything currently on the page, or View→Zoom Full to display the entire workspace.
Colors of objects in a schematic or symbol are set using a limited color palette, with the various colors having particular meanings. For example, nets (which have electrical meaning) are drawn in a different color from lines (which are simply graphical). A color map is used to choose which color to draw a particular object in.
There are several color maps provided with gschem, and you can switch between them from the View menu. It is also possible to change the default color map or create your own. For more information, see Configuring gschem.