You can find more detailed information on male multiple orgasms in the book "The Multi-Orgasmic Man" by Mantak Chia and Douglas Abrams.
The book offers detailed descriptions of the biological side of the ejaculation process. One chapter offers a number of solo exercises (masturbation techniques, yes) you can practice, as well as very detailed breathing exercises and positions. The book offers advice for both straight and gay couples, and for both younger and older couples. There's also a chapter on preventing premature ejaculation and on the relevance of penis size. Finally, there is an interesting section on fertility and raising sperm count.
Even though the original node offers a great summary of the technique, the book will offer a great amount of detail for anyone who wants to dig a little deeper.