To Add Assignments of a Material via the Material Assignments Dialog

In the Material Assignments dialog, click the New button.
The New Assignment dialog opens.
In the Levels field, type the level(s) to which you want the material applied.
In the Colors field, type the numbers of the color(s) to which this assignment is to apply for each specified level.
Click the OK button.
The New Assignment dialog closes and the new assignment is added to the assignments list.
(Optional) To make additional assignments of the current material, repeat steps 1 to 4.
When done, click the OK button in the Material Assignments dialog.
The material is applied to elements on the specified levels that are of the defined colors.