Side: Left and Right depend on the wall's direction, assuming you are standing at the start point and facing the end point. To show the directional arrow, check Show Direction on the Wall page of the Properties.
For details on materials, see Materials
In this example, the walls were created in the order shown. The Right sides of the walls have a brick material, and the Left sides have a grid pattern. 
Manage space
Manage content
Integrations