Thomas (University of Aarhus, Denmark) Olesen 
Developing Performance Support for Computer Systems [PDF ebook] 
A Strategy for Maximizing Usability and Learnability

Developing Performance Support for Computer Systems: A Strategy for Maximizing Usability and Learnability provides detailed planning, design, and development guidance for generating performance support for new or upgraded computer systems. Performance support includes documentation, online help, coaches and wizards, training, and other materials necessary to enable users to perform their jobs more efficiently and effectively.
This volume offers a strategy for maximizing ease-of-use and ease-of-learning through an integrated performance support systems approach. The text provides how-to guidance throughout that developers can apply directly to the design of their performance support tools and products. Rather than cover a few specific topic areas, it examines the entire spectrum of performance support. The book explains how to match performance support methods to task requirements, gives an overview of important user characteristics, and provides general guidance for presentation, layout, formatting, media selection, the use of color and icons, and accessibility. Evaluation checklists are included in the appendices and are also available online.
Although this book primarily addresses the development of performance support for large software systems, the principles and approaches are valuable for any systems development environment.