Wire Frame
You can change the presentation method of the model to wire frame and shaded in turns by clicking the Shaded/Wireframe button on the tool strip.
You can also select Rendering | Render Style | Wire Frame.
When you view the model in the presentation method Wire Frame, you can temporarily remove hidden lines by using the keyboard command Ctrl+H. The hidden lines are restored when you rotate the model, for example.
You can select the color of the lines in the wire frame model in graphics settings.