I need to take an independent lie detector test and would like advice as to how I go about it.

The best advice I can give you is to retain a competent attorney, probably a criminal defense attorney, to guide you through the process of undergoing a polygraph examination. Polygraphs are generally not admitted into evidence because courts do not consider polygraph results to be "reliable" evidence. Sometimes, a prosecutor will insist an individual take a polygraph to corroroborate their version of events as a condition of a plea-bargain. Or the prosecutor may request a polygraph to test a person's reliability if the individual has agreed to be a witness in court against another person. Many defense attorneys, when faced with having a client undergo a polygraph, will arrange to have their own expert test their client first. If the results are favorable, the lawyer is more comfortable having the client undergo a polygraph administered by law enforcement. In short, I recommend that you confer with a criminal defense lawyer in your area about whether you should undero a polygraph examination, and if so, who should administer it.