When you continue your education is up to you. Some students choose to work for a while and then to attend graduate school. If you're considering postponing graduate school, or if you haven't decided whether it's right for you, contact the school you want to attend to see whether you should take your graduate exam now or wait until you're ready to enroll.
Some schools accept only scores for tests taken within a certain period before enrollment.
However, if that isn't an issue, it might be a good idea to take the test while everything you learned is still fresh. If you're looking for help in preparing for your graduate or professional exam, be sure to check out all the sample tests that are available. The test manufacturers offer study helps and practice tests to help test-takers prepare. Online samples and practice questions are also available. If it's been a while since you finished your undergraduate work, consider taking some refresher courses before taking your graduate or professional exam.