Mistake 1 and 2: Leaving Questions Blank and Poor Time Splits
JAMB has no negative marking, so a blank answer is a guaranteed zero while a guess has a one-in-four chance. Answer everything, even if you must guess in the last minute.
Many candidates also spend half their time on the first subject. Divide your time by the number of questions and check the clock at fixed points.
Mistake 3 to 5: Reading, Calculating and Changing Answers
Rushed reading turns 'which is NOT' into 'which is'. Underline the key word mentally before you look at the options.
In calculation questions, work out your own answer before you look at the options, because the options are designed to tempt you. Change an answer only when you can state exactly why the first one was wrong.
Mistake 6 and 7: Skipping Practice on a Computer and Ignoring Weak Topics
Typing, scrolling and navigating are skills. Practise on a screen so the interface never costs you seconds.
Finally, track the topics you miss and revisit them every week. A weak topic you ignore will show up again in the real exam.