A good place to start before simply registering for school and spending a lot of money is to know what it actually is. A polygraph is a way of determining what someone is lying about or if they are to be caught in a lie. The first thing to know is how a polygraph works. A polygraph will record physiological information from three different portions and systems of the body. The test itself is broken down into three parts.
The test to determine a lie is not as simple or easy to understand as it may appear on television or in a movie. Consider how people go about cheating in order to alter the results of a polygraph exam. Many of the methods that people are familiar with are in fact not true and will not in many cases alter the test. In many cases, the actual test may be misleading as the person may provide false positive results, not through cheating, but because there body does not respond typically when a lie is being told.
All of these are things that one will need to learn and know in order to get into the field of lie detection. However, what many people do not consider is the fact that there are multiple methods and machines to take into consideration when training or looking to get into the field of lie detection. Being able to know if someone is cheating on their wife is one of the many cases and circumstances that one will encounter. Getting back to the equipment, however, it is all dependent on how up-to-date as well as technically savvy the company you are looking to work with is. Make sure before getting a job in lie detection that you know what you will be doing and how to use the equipment.
The main thing that it comes down to is being able to get a certification from an accredited school. Not only should you look into the school itself, but look into as the reputation of the program and those who have had success in finding work from it.