My method is to get some hands-on experience first with the technology: Tutorials, Getting Started pages, the first chapter of a book. The fumble for some time and getting exposed to various sources of information. Then I take a book and skim it from start to cover, stopping at interesting bits. Then I reread various parts.

Sometimes I start with reading the books. But I already known I won't retain anything deeply. But it will gives me all the right keywords to learn more about the technology.

It always amaze me when I see fellow programmers struggle with problems that could have been solved easily by just reading that introductory book on the subject.