Where is it?
The Decal Types dialog displays the new decal name and its attributes.
Click (Browse) to navigate to the file. Revit supports image files of the following types: BMP, JPG, JPEG, and PNG. See Best Practice for Storing Image Files.
See Decal Attributes.
Now you can place instances of the decal type in the building model. See Placing a Decal in a View.
In Revit Structure, you can only define decal types. To place decals, use Revit Architecture or Revit MEP.