Step 2: Extend an Existing Framework
The easiest way to create a custom framework (document type) is by extending an existing built-in
      framework, such as DITA or DocBook, and then making modifications to it.
    - Open the Preferences dialog box and go to . Add the path to your custom framework directory in the Additional frameworks directories list and click OK or Apply to save your changes.
- 
          Go to the Document Type Association preferences page and select an existing framework configuration (for example, DocBook) and use the Extend button to create an extension for it. Step Result: This opens the Document Type Configuration dialog box where you can define the set of rules and settings for your custom framework. 
- Give the extension an appropriate name, select External for the
            Storage option, click the browsing button ( ) to specify the location of your custom
          framework directory. ) to specify the location of your custom
          framework directory.
- Click OK to close the configuration dialog box and then OK or Apply to save your changes.
Results: You now have a fully functional framework that you can continue to customize.
