for subjects like maths or chem i would just spam past papers...literally. Maybe do like one after you get back from school and one in the evening? Should take like an hour per past paper. For content heavy subjects, in particular SOR, i also just spam practice writing. Do as much practice as you can, on the train, during your free period, whenever. Theres no real point in reading your notes over and over again if you cant apply it; subjects like english in particular or any subject that requires the integration of a stimulus require this skill so practice practice practice.