There are three main components:
I recommend bushberg's book as your primary resource. Try to read it over the course of your first two years in radiology residency. Yes it's long, over 1000 pages. But each topic is well organized, clearly explained, and doesn't repeat the others unnecessarily.
In contrast, the digital modules are often disorganized and repetitive and take just as long if not longer to read each topic. Don't let the card flipping with no pages numbers fool you - I printed one module and it was over 50 pages, the same as the bushberg's chapter. Some modules are better than others, and a couple they redid lately are quite good, so maybe in the future they can be a primary resource.
Also try to attend any physics lectures from your program or conferences or review sessions.
Huda's review is also helpful.
For all of these methods - do not get bogged down in esoteric complicated details. Just try to understand the main points and concepts. They are things you have to see multiple times in different forms but eventually make sense. The details are for people doing a phd in mr physics. That's not us. We have an incredibly broad topic range, but only need the key concepts from each.
That applies to the whole exam actually. I see this over and over again, not just with the well meaning lectures mentioned above, but with almost all the practice tests. Questions that are unanswerable are not appropriate for the test. And there are a bunch of statistical and standardizing they do with the questions so that the can determine who knows and does not know the material. Even if a question like this is seen at the exam, it may be thrown out or may be a question they are just trying out to see if it's reasonable.
Also read the last chapter in mettler for more key safety stuff.
This is a major component of the exam so make sure to put in the time on it. The majority of the quality and safety material is from the guide from the abr. it's around 65 pages and can be read in a few hours. I would read it twice: first about a month before the exam and then read it again a couple days before so it's fresh. You need to know the types of charts, various quality definitions, the different organizations involved, etc. Read it carefully and know the exact definitions.
The best resource I found was mandell's core book. It is well written, thorough, and has the key concepts and details on the key entities. It's excellent and will do you well to read it. There are several other new core books out there that I didn't have time to read but may be helpful if you have time.
Of course learning as much as you can during your regular rotations will serve you well.
There are several sets of practice questions, the most popular including rad primer and qevlar, and many old board study case sets. Frankly I didn't find any of them that helpful. I think they are often focused on the wrong things, badly worded, have multiple arguably correct answers, etc. that said, educational research has repeatedly shown that practice testing is the most effective way to learn, so it would still be of benefit to go through them or others if you find better. But don't get bogged down in the details of any one question, rather use them as a guide and learning tool to teach your brain.
That is not to say there are no details. The test does ask a number of specific details on various things. But at some point you go too far down the rabbit hole where it is just meaningless trivia.
A few things I would have liked to know better
You have the choice of Tucson Arizona or Chicago Illinois. Tucson has several nice hotels within a short walk from the office and was a pleasant experience. I haven't been to the Chicago office but I'm sure it's fine as well. I think the main difference for us is the flight. Depending on where you live,the flight time duration, cost, and layovers may be quite different. Hotel cost may also differ. The time difference could also factor.
Try to get there an extra day ahead of time to make sure to account for any unexpected delays. Also I found the extra day here just before was perfect to sleep in, review a few things in the morning, and relax later on. You need a refreshed mind and body for the test. Have a good dinner and sleep As much as you can.
For the questions that you know the answer immediately, select it, but then slow down for a moment and re read the question and other options to make sure you really understand what they're asking. Obviously be very careful to not miss any "not" or "except" kind of logic or any answers that are even more likely than the one that first caught your fancy.
For the questions you don't know, try to eliminate options that are definitely not the right answer. If you can narrow it down a bit your odds rise significantly. If you've never even heard of something, it's less likely to be the right answer (I think!). Then just pick an answer, flag the question, and move on. Don't spend forever on any single question. It's much better to make a thought through guess at every question than to try to get the first 80% perfect and then have no time to even look at the rest. Impossible or badly worded questions get thrown out in their analysis.
At the end, with whatever time you have left, go back through the flagged questions and see if you can improve your answer. Sometimes some time to mellow the back of your brain makes things clearer. Sometimes a clue to the answer may have even been given away by another question. At the end of the day, you just need a certain percentage right, and the majority of people pass the exam, especially those that put a reasonable effort into preparing.