Your Nine Subjects Are Not Equal
English and Mathematics decide whether you can proceed to university at all. They need daily attention. Your other subjects can be rotated through the week.
A Simple Weekly Rotation
Monday and Thursday: Mathematics and English. Tuesday: Physics or Economics. Wednesday: Chemistry or Government. Friday: Biology or Literature. Weekend: past questions and weak points. Adjust the subjects to match your own combination, but keep the rhythm.
Practicals and Essays
Do not leave practicals until the last term. For science subjects, learn the apparatus, the common errors and the labelled diagrams early. For essay subjects, write one answer per week and have a teacher mark it. Marks in WAEC are lost more often to poor expression than to ignorance.