Through the Select & Display Style window several options can be specified for volumes, surfaces and cuts. Among these options volumes, surfaces and cuts can be switched on and off, their color properties can be changed, and their transparency too.
Other interesting options which can be changed are the style of the set and the width of the elements' edges.
From this window, volumes, surfaces or cuts can be deleted or their names can be modified.

Select Window->View style... using the menu bar or clicking on

Our model only has 1 layer. We will create a new layer with some elements (in fact in postprocess instead of 'layers' are 'sets', but are similar concepts)

Press button Send to->New set.
Select some elements.

Press Escape.
A window appears asking for a name. Enter 'Aux'.
Press Accept.

A new layer is created with the selected elements. Now we will change the color of the new layer.

Click on the colored square next to the layer name. A new window is opened. Select a new color.
Press Apply and then Close.

Let's play with some visualization options

Select Body Lines in the "Style" option, at the bottom of the window. You can also do it clicking on in the St column or the same icon in the main window, but then it only affects this set.
Click on the icon of 'Aux' layer in order to switch it off.

It's possible to draw preprocessing information, for example the geometry.

In Draw Model option select Geometry

Now our model should look like this:

NOTE: The View style window can be integrated inside GiD interface, just double click on the upper bar of the window. To tear it off again, double click the upper bar again.
NOTE: Mesh styles can also be changed clicking on the icon , placed in the left icon bar. This style affects all sets of the model.

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