audit evidence was my biggest issue too, much harder than anything on FAR. I think it's one of those areas where experience in auditing would make it easy but without experience it's very difficult.
part of the reason is because it's so difficult to teach, at least traditionally (by reading and watching lectures). there's too many possible permutations of procedures and events and accounts and documents and orders to even begin listing them, or memorizing them. so the best they can really do is give you a very general framework – basically, the types of audit procedures you can do, tracing/vouching/confirming /recalculating etc, the assertions, and some common documents. but then the MCQs come in and they're insanely specific and it feels impossible.
I have AUD tomorrow and I'm still not nearly 100% comfortable with them. I think the best you can do is just MCQ, MCQ, MCQ. I know it's typical advice, but it works better than almost anything else. the more comfortable you get with the procedures, assertions, and documents, just by repeated exposure, the easier it gets to read and interpret the question and each answer. I would recommend doing the MCQs in the mode that gives you immediate feedback, and what you want to do is try to get the answer right obviously, but even if you do, click each wrong answer and read the explanation on why it's wrong. this way you get exposure to 4 different procedures searching for evidence in 4 different ways.
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