First determine which are tough subjects and which are not.then On the tough ones,hold ur text book and only point out and focus on the major conceps ,dp go too detail... Like when u study ask the following What is this? What does it mean? What is its use/functiom? What is its property/xtics? What is the concept behind(make it simple and understanding for u). Also read something and take notes(not coping the exact thing on there) try to understand and analyse it in ur mind and wrote what u understand.that way u will more likely to remember it on exam I hope it may help u 😃