Below is an outline of how I studied and prepared with a few tips as well. I got a 38 (PS14 VR11 BS13). If you feel like you are struggling I would recommend getting a personal tutor if you have the money. They are often cheaper than the big name review courses and can help you attack your weaknesses better, as well as come up with a study plan that can help you. I used Next Step Test Prep. One of my biggest tips is to review the material and make sure you feel totally comfortable with it before starting to do the practice exams. There is no point in wasting a practice exam if you aren't comfortable with all the material yet.
I mainly used ExamKracker's as I found this to be the most concise (my tutor recommended this and I looked at some of the others and he seemed correct with this assumption). The other review books I find go into a lot more detail than necessary. Now if you feel really weak in one area you may want to get another review book that goes more in depth so you have a better general knowledge about it, but I found EK to give you the essentials. So for the first month and a half my day would look like this:
-read a chapter in one of the subjects of EK and do the problems in the reading and the chapter exams at the end of the book
-review the chapter I read the day before by skimming the pages and taking a second look at anything confusing as well as quickly going through the questions paying more attention to the ones I had missed
-do 2 verbal passages from EK 101 Passages or TPR Verbal with a 15 minute timer (this is shorter than you get on the exam but I found it helped me think and read faster)
-review the verbal passages I had done the day before
This would take anywhere from 3-5 hours. Then after the 5th day I would have a review day where I would review the four previous chapters I had read (skim through the pages and look at the questions again) and do two more verbal passages. I also took a break day once a week.
One thing I advise during this time is to do a different subjects (Orgo, Bio, Chem, Physics) everyday so all the subjects are always fresh in your mind. I would normally do one chapter from each book and then my review day I would review these four chapters.
A few notes for Verbal. First, practice AND review. Make sure to review the questions not just after you do the passages but the next day to remind yourself why you got a question wrong. It might seem stupid at first and like it isn't helping but I noticed when I forgot to do that I was not improving but when I started reviewing the day after I noticed I was doing better. Second, I never felt like I was improving at Verbal but my scores were, so don't get discouraged if you don't feel like you are getting better or learning how to master Verbal. I feel a lot of the Verbal strategies you learn while practicing are almost subconscious. You just start getting a feel of what looks like the right answer even if you aren't 100% sure, and it is often right. I could not tell you "I know this is the right answer because X" but after doing so many problems you just start getting a sense of what the right answer is even if you can't really explain why (I know this is kind of a frustrating response but its what I found). Obviously if you aren't getting more correct answers in your practice then you should reevaluate what you are doing and maybe try something different, but don't expect a huge "aha" moment when it comes to Verbal. Third, one tip my tutor told me and it seemed pretty true is to go with your gut on Verbal. It is one reason why I practiced with 7.5 minutes a passage even though you get around 8.5 minutes on the real thing. The more you think about a question the more you start validating wrong answers and tripping yourself up (which is what the exam writers want). If you find yourself struggling and toiling with questions try just going with your gut reaction to the question. See how it works. It may not work for you but it definitely helped me. Lastly, get two verbal practice books (I suggest EK 101 because it has good questions and TPR verbal because it has good passages) and keep changing between the two once you feel like you have plateaued with one. They help you practice slightly different strategies so it is good to do both.
So after this month and a half I took the 5 Self-Assessments. I took the Chem and Physics on the same day and the Bio and Orgo on the same day and then all the Verbal on one day. I did not know how long they were going into it so I might recommend doing just one a day as it was a lot. Definitely split up the Verbal. 21 passages is just too many for one person to do in one day without getting extremely fatigued and frustrated. I did it all in one day and got 88% correct on the first 14 passages and 64% on the last 7 passages, so fatigue definitely played a factor and I wasted good practice passages trying to do them while exhausted. After each Self-Assessment I spent 2 days reviewing all of the questions on that Self-Assessment, paying more attention to the ones I missed or guessed on. Through this time I was also still doing 2 verbal passages a day and reviewing them the next day (THIS IS KEY FOR VERBAL).
After this the way my schedule worked out I had an extra week or so in my study schedule I spent just taking one subject a day and skimming through the whole book and the questions making sure to brush up on anything that I still felt was weak. I felt weakest on the Bio body systems so I got the TPR and Kaplan Bio books and read the body system chapters to get a little different view on them. I also continued the two daily verbal passages.
This led me up to about a month before the exam, when I started taking the AAMC practice exams. I took two practice exams every week with two days in between and a rest day each week. During those two days in between I went through the practice exams each day looking at every question and paying close attention to the ones I missed or marked. I then took one chapter from each subject book (Orgo, Chem, Bio, Physics) and spent just about 20 minutes each skimming the chapter and looking at the in-reading questions to make sure I still felt comfortable with the material. For Bio, which I felt was my weakest science, I would actually just reread a chapter every day in between practice exam days since the EK chapters are not too long and Bio is something you learn more by just reading material on it rather than doing questions. While this short review of each chapter may seem insignificant I found it important for me to at least look at the material so it would stay fresh in my mind since the practice exams don't cover all the material you have to know. Taking a month to just do practice exams is a long time that you may forget some details that the practice exams don't cover, which is why I did this quick daily chapter review. I also bought a book called Kaplan 45 Advanced Prep that had some really tough practice that I would try on these between exam days but I really wouldn't recommend it unless you feel like the normal practice isn't tough enough. I didn't find it that helpful and it was a little discouraging. Lastly, of course, I would do my two verbal passages. These days would take about 4-6 hours.
So this led me up to the last two days before the exam where I just relaxed and tried not to think about the exam. I had made a study guide with formulas and facts/terms I often forget earlier that I just glimpsed over once or twice these two days before, but other than that I just tried to relax my brain. The MCAT is like running a marathon, there is no point in practicing a ton the two days before. You have prepared for awhile for this and it would only hurt you.
So that is what I did to prepare for the exam. Hope this helps. I know studying to retake it might be a little different if you have already used up all the AAMC practice tests and stuff but I hope some of this advice can help you. Personally I would say to stay away from the review classes such as Kaplan and Princeton and stuff as I feel each person learns a little bit differently and might have their own things that work better for them. I got a personal tutor (from Next Step Test Prep) and it was helpful but really if you can plan your schedule and stick to it studying on your own is really the best way to learn it. A tutor can help you come up with a schedule and answer some of your questions but overall it comes down to just sitting down and doing the stuff.
If you have any more questions feel free to ask! Good luck!