Do you have experience coding orthopedic surgery? If not, I probably would suggest not taking this exam.
Do the study guide and quizzes at the end of each. Go back and review/study anything you get wrong.
Do the practice exam next. Go back and review/study anything you get wrong.
Once you feel like you could sit for the exam, take the practice exam in a timed "mock" test as if you were sitting for the real thing and see how you do.
Do the orthopedic webinars the AAPC offers, just keep in mind the year because there have been orthopedic changes through the years.
AAOS/KZA resources are helpful however, be sure you understand if those are geared towards CPT or CMS rules and compare to what the test question scenario is.
Don't waste time on the test in reading huge op reports if the question has nothing to do with the procedures and maybe only is a "basic" question. I would reccomend looking at the final question and answers first to see what you should be looking for, it's a time saver. I took this before the new formats and reduced # of questions so I can't speak to the new procedure.
Make sure you know and understand bundling, separate procedure codes, and how to find codes and references quickly in the books. Anatomy is your friend - know and understand it.
Search COSC, orthopedic certification, orthopedic exam, etc. to find related threads in here for tips. Example:
https://www.aapc.com/discuss/threads/cosc.186604/?view=date#post-510532