After defining the geometrical elements, proceed to define the unit cell using the Cell → Define Cell menu. In this step the material is assigned to the layers. As many layers as different Z coordinates found in the geometry are defined.
In this example the Foam material is assigned to the layer. The cell is defined with the dimensions set as 1.0 centimeters in the X axis and 1.0 centimeters in the Y axis. The number of replications of the unit cell are 12 cells in the X axis and 12 cells in the Y axis. The skew angle defines the angle of displacement from the Y-Axis to the replication cells. The assigned value is 63.5 degrees.
It is necessary to press the Save button to save the changes.