Purchase study aids online. Research the most popular and well-reviewed test preparation books and CDs on your favorite online book vendor's website. As the test-taker, you can use your new books alone during your allotted study time, or you can hire a private tutor to go over the material with you. Online study guides are also available if you prefer to keep it digital.
Go to the official websites for the SSAT and ISEE, and take a look at the interactive sample tests. Both sites offer extensive information, with questions, answers and basic information about the scoring. You should become familiar with the format and grading technique of the test you will be taking so that you know what the penalties are for an incorrect response, and how much time you will need to allot for each question and subject section, for example.
Set aside a certain number of hours each week to go over the subject matter that pertains to your test. It often helps to recreate the actual exam environment by timing yourself in a private room and maintaining silence during guide review and practice questions. Some days, you may prefer to study with a friend who is also preparing for the test.