There are many commercial study resources.  

• Make sure to choose a resource that offers multiple practice exams.  You will want to challenge a practice exam as a pretest and later challenge additional practice exams to guide your study and ultimately to determine if you are sufficiently prepared to challenge the state exam.
  
  
• Read all of the "How to use this resource" section in the commercial resource you purchase.
  
  
• Read all of the test taking hints and tips the resource offers.