There are several ways to study for a six sigma test, but it will all depend on a few things such as the way that best motivates you to learn about the six sigma technique, the amount of information or knowledge that is currently stored in your mind right now, the type of environment that best suits your mood and whether or not you will need particular materials in order to make studying easier. Some people are confident in their abilities and stock knowledge, so they can do with just a quick review of their notes or they buy some sample materials online and review on their own.
Others still want to fine tune their knowledge by engaging in online or web simulated review or mock exams (perfectionists much?) which one can take several times until satisfaction of exam results is achieved. Other people who are a bit doubtful about their skills or feel the need for a more high intensive review might choose to enroll in several review courses which can be a classroom type of review with a teacher leading you along the way. Those who are very social by nature may benefit from a study group with friends and fellow test takers, bringing with them their review materials as well as trading information and clarifying tricky bits of the sic sigma process. Some who are in need of human help but are not comfortable or does not work effectively with a study group may choose to hire a tutor or an expert with a good background in six sigma in order to study and review for the test itself.