If modifications to a custom skin package are to be more extensive than you can achieve using the Skin Administration page (fonts, colors, and images), you need to know what properties or CSS classes you want to modify from among the hundreds of properties that exist in a skin package. One way to do this is to use a browser developer tool such as the Firebug Add-on for Mozilla Firefox.

Open My webMethods Server in the browser and navigate to a page that uses the skin package you want to examine. Using the developer tool, you can explore the user interface and determine the CSS classes used to display it. With this knowledge, you override values in the parent skin through the use of extended.css or extended.csi files in the custom skin.