Before I write anything allow me to mention that I did do well on the Step 1, but there are many who have done much better. Therefore, please take this advice with a grain of salt. Such advice never fits everyone and there are many other ways to prepare for the USMLE Exams. Finally, I studied based on the traditional US curriculum (2 years preclinical, 2 years clinical) so the time available to me may not be available to you; take that into consideration.
The best advice I can give is to study well during the first two years of medical school. I found that a strong foundation really helps get through the study material efficiently and is essential to doing well on the test.
Second, planning is everything. Do not begin studying before you have divided up your time based on your strengths and weaknesses. Some people are so stressed out by the time issue that they forget to stop and think. Don't do that because it wont help you. In my opinion it is wise to devote several days to planning in order to maximize the efficient use of the time you have. Also, be aware that you may need to make changes as you go along. Constantly reevaluate your progress and make sure you are meeting your goals - plan this reanalysis into the initial schedule. Finally, you should try to get example schedules from previous grads or your peers, they are very useful as a base for your own planning.
With regards to doing a course, I definitely like the idea. I did a course and I think it helped me a lot. The fact that someone had already organized the information for me and analyzed many of the possible pitfalls on the test saved me a lot of effort and time. However, I do know of several people who did excellent without a course; you should do whatever works for you.
Finally, it is best to get through all of the available question banks prior to doing the test. I cannot stress this enough - and yes I mean all the questions banks and not just two. It is my belief that there is a direct correlation between the amount of practice questions you do and your score. The more questions you do the better your score will be. Moreover, there are only a set number of ways to ask about many topics, I believe that if you go through all the question banks you will probably see most of the options and so not be surprised on the exam.
Do not forget to do full mock exams. A large portion of doing well is being able to concentrate for a long period of time and properly allocating your breaks - if you don't practice this several times before the exam you will be in shock (doing 8 sections one by one is not the same as doing 8 sections under the time constraints of the test). If you really want to go crazy do more sections then there are on the exam (10 for example) and then the test will be even easier.
Another important point is to have someone motivate you and monitor your progress. I found that when you have someone following your progress you get more done and you remain more balanced throughout your preparation. This is especially true towards the end of the preparation when you're tired and you just want to get the test over with.
Finally, the proper book for the USMLE Step 1 is "First Aid for the USMLE Step 1". If you use this book, do all the question banks, and follow the above instructions you are very likely to succeed on the exam.
Final words: its tough, but doable.
USMLE Step 1 Exam Tips
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