6.2.2 - Assign Code Sets
Step Description:
Code Sets control how the assemblies that will show in the cross section views will be displayed. They control items such as how the points, links, and shapes appear as well as labels.
Florida DOT has a Code Set Style that is shipped with the state kit.
To select a different Code Set, first select the Corridor in the drawing.
In the Contextual Ribbon click the Corridor Properties button.

Go to the Codes tab then select a different Code Set Style from the drop list or modify the code set by selecting the Edit Current Selection button next to the drop list.

AutoCAD Civil 3D 2012 User's Guide reference:
User's Guide - Corridor Modeling - Corridors - Managing and Editing Corridors - Editing the Code Set Style
For more information watch the video below:
Roadway Model (WMV)