i don't have much to contribute in terms of specific rules. I believe that each person has its own set of rules that work for him or her, and trying all of them may take too much time and be cumbersome.
however - I do think that there is a studying strategy that may help a lot in eliminating stupid mistakes: doing the same questions again and again with long intervals between (both in terms of time and amount of practice performed between).
this can be done with most books (I did it with
OG) - i solved all questions once. then after a day or so, did the all over again (both those i succeeded and those i failed) - and checked if i made the same mistakes twice. then at the end i identified about 30 questions in which i had most wrong answers, and made them again.
this is also true with gmatprep. once you did your 2 tests - do them again. first - you might encounter more questions which is nice. second since you get more questions right, you are likely to get harder questions each time you redo the tests - this is good practice. third (and most important) - when questions are repeated you can check whether you learned from your mistakes or not. this may help you analyze your weaknesses, help you avoid stupid mistakes and boost your confidence (but don't rely on the outcome of repeated tests as an indicator of true score. and don't rely on those repeated practices in terms of time management)