Logging a mistake takes a minute. Actually reviewing the log — reading back through it, spotting what repeats, and deciding what to do about it — is the step most students skip, which means the log they kept so carefully never changes what they study.
Do this the night before, not the morning of
Reviewing your error log the morning of a practice test just makes you anxious and doesn't leave time to act on anything you find. Do it the night before instead, with enough time left to actually redo two or three of the questions you flag.
Step 1: Sort by error type, not by date
Your log is probably sorted chronologically, which is the least useful order for reviewing it. Sort or filter by error type first. You're looking for one thing: which single error type shows up most often across the last two or three tests. Not which category, not which subject — which reason.
Step 2: Cross the error type with subject
Once you know your most common error type, filter to just those rows and look at the subject and category column. "Concept Misunderstanding" spread evenly across ten different topics tells you something different than "Concept Misunderstanding" showing up six times, all in the same category. The second case is a study-time decision with an obvious answer — that one topic — while the first is a broader review habit you need to build.
Step 3: Pick two or three questions to actually redo
Not twenty. Pick two or three unreviewed mistakes that best represent the pattern you found in step two, and redo them from scratch — no looking at your notes on how you got it wrong the first time. If you get one wrong again, that's real signal that the gap hasn't closed yet, not just a logging exercise.
Step 4: Mark them reviewed
Update the "Reviewed?" column once you've redone a question, whether or not you got it right the second time. This is the column that tells future-you whether a mistake is still open or already handled — without it, every review starts from zero and re-covers ground you already closed.
What "done" looks like
A good pre-test review takes fifteen to twenty minutes: five to sort and find the pattern, ten to redo a couple of questions, five to jot down the one thing you're watching for on tomorrow's test ("check for extraneous solutions," "read the last line of the question twice"). That's it — it doesn't need to be longer to work.
If this is the first time you're doing this and don't have a log yet, start with how to start an error log. If you already review weekly and want a tighter routine than "the night before a test," see the 15-minute weekly review.