Pay attention in nursing school. This may seem oversimplified, but the better you do academically, the less stressed you'll be when the actual test comes around. That is, if you learn the material in the first place, you won't be trying to play catch-up in your senior year and beyond.
Take a prep test while you are still in school, such as the Mosby Assess Test, which is a set of NCLEX-style practice questions. These pre-tests can really show both your weak and your strong points, and give you a point to focus studying from. Also, doing it while you're still in school allows you to get help from your teachers while they are still easily accessible.
If you are unclear on a concept, be dogged about learning it. Whatever it takes, if you know your weaknesses, hone in on them and don't give up. Eventually, many of them will become clear to you if you come at them from a couple different angles. And 90% of learning is perseverance.
Seek new opportunities in clinical. If you can learn concepts hands on, you will be a lot more likely to remember them later when you study. Look up your patients' labs and find out why they are the way they are. Look up your patients' meds and learn the side effects, proper dosages, etc, even if they are meds you've seen a hundred times. The key to learning pharmacology is (sadly) repetition.
Get a good NCLEX-RN prep book early in your academic career. It is never too early to start reviewing and practicing answering NCLEX-RN style questions. Getting used to the way the questions are worded is one of the best prep tools there is.
Take an NCLEX-RN prep class above and beyond what your school has to offer. Many independent institutions (such as Drexel University College of Nursing and Health Professions http://passnclex.drexel.edu/) contract with nursing schools and/or student groups across the United States to provide 4-day review courses to prep for the test. Some even offer reimbursement of test fees if you fail. If your school does not have this opportunity, seek it out elsewhere.
As soon as you graduate, set up your test. Your school should be able to help you out with this, but it's very important that you do it soon after graduating, while the knowledge is fresh in your head.
Studystudystudy. Use more than one source for review information, and do as many questions as possible before your test. If you want to be confident going into the test, count on answering at least 5,000 test prep questions prior to the test itself. This takes a long time, so budget appropriately.
At some point before your test, sit down and do 265 questions in a row. Answering that many questions in a row takes discipline and stamina, but bear in mind that you can answer 265 questions and pass the test, so make sure you can.
Take computerized tests for prep if possible. Hopefully, your nursing school has already done this for you, but if not, get a review book with a CD-ROM in it, which will allow you to take the test on the computer, which is how you'll actually be taking it.
Drive to the test site the day before, especially if it is far from your home (i.e., in unfamiliar territory). This will cut down on stress the day of as you will already know where the test site is.
Try and relax and have fun the day before the test.
Your brain needs glucose to operate properly, so have a decent breakfast with the major food groups represented on the day of the exam, even if you are not hungry.
Make sure you use the bathroom before you take your test.
Ask the proctor for earplugs. They really cut down on the distraction of ambient noise.
Sit down and familiarize yourself with your computer station. Find the calculator. Complete the tutorial.
Take a moment, close your eyes, clear your mind, and visualize very clearly what you are about to do. This is also a great time to pray.
Calmly start the test, taking one question at a time and allowing each question to hold your attention completely. Remember that the test will shut off automatically. This can be quite jarring, but hey, you're done!
Get in your car and go buy yourself a treat.
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