To Change the Default Transparency Assigned to a Layer
Click Home tab Layers Panel Layer Properties Find.
In the Layer Properties Manager, under the Transparency column, click the transparency setting that you want to change.
In the Layer Transparency dialog box, from the drop-down list, choose the percent transparency that you want to use as the default for objects on that layer.
Note:
The value that you choose is used for all objects on the layer that have a ByLayer setting for their transparency property.
Transparency is not displayed automatically. If you want to display or hide the transparency of objects, click the Show/Hide Transparency button on the status bar.