You can make every object on a particular layer the same color.
Using single-color layers can help you visually keep track of which objects are on which layer. Designer lets you mix single-color layers and multiple-color layers in the same drawing.
By default, a layer is multicolored. If you limit a particular layer to a single color, all existing objects and all subsequent objects are filled with the single color. You can use the current default layer color or click the Layer Color button to choose a different color.