In addition to access to a copy of Section 1.1, “Bob Stayton's DocBook XSL: The complete guide”, you will need to know your way around these tools to work effectively on stylesheet customization:
XSLT, the language in which the DocBook-XSL Stylesheets are written. Doug Tidwell's book XSLT (O'Reilly, 2001, ISBN 0-596-00053-7) is an extremely valuable tutorial. See XSLT Reference for a summary of the language. There are also some XSLT debugging tools, but the present author has not tried them.
XSL, also known as XSL-FO (for Formatting Objects), is the language used to specify printed output. We don't recommend trying to learn this language, which is considerably bigger than XSLT, from the standard. Fortunately, Dave Pawson's book XSL-FO (O'Reilly, 2002, ISBN 0-596-00355-2) is a well-written tutorial.
A schema-aware text editor helps maintain the
correctness of XSLT and XML files. We recommend XML document authoring with emacs