Find out which test you are going to be receiving. Discuss this with your boss or management, as you have the right to know and can request this information.
Take a practice test online for each of the test sections you are taking. Finish the test and read your results to find out if you passed.
Look through your questions and find areas where you need additional study. Each question has a description of what skill it is testing. For example, if you missed six questions in the logical reasoning test that featured comparative analysis, you may be weak in that section.
Use your textbooks and work place handbooks to study and practice in weak areas. Use the handbooks to remind you of any workplace guidelines you must follow. Pick textbooks specific to the area you were failing, such as an algebra book for the numerical reasoning test.
Take another practice test to analyze your progress. Continue studying your weaker areas while not neglecting your stronger areas. Don't let strong areas of knowledge become weak due to lack of practice.
Repeat this process until you can regularly achieve the score on the Kenexa test you want to achieve. Passing requirements vary depending on your job.