you should make it a habit to constantly go over things you've already learnt , not in depth as it should just be done to refresh your memory. So when you sit down and study you can spend more time cementing your knowledge by putting it in practice by doing questions .
i dedicate 3 1/2 hours a day to hw and study. I spend 1/2 an hour dedicated ti each subject. 15 mins generally goes to hw and the other 15 mins is just quick revision of reading notes and trying to recall definitions. I’ve written out all the definitions weve done so far on flashcards so its quick and easy to revise them. i think it would be good to do the same for experiment. this technique mainly applies to sciency subject, and i chose to study these subjects as theyre easy to study for. I do ordinary level english/irish/french as i hate studying for them but id recommend havi a list of quotes on sheets for every poet/drama for english that make it easy to revise them and a list of key words in a topic and good phrases for irish/french to learn off for the essays. I do HL maths and applied maths so I spend my 1/2 hr just doing hw questions and extra questions on topics that i struggle with the most.
I have an actuvity after school every day for about an hour each and i usually get 3 hrs study done by dedicating 1/2 hr to each subject everyday and i go on my phone at around 9 and after school when Im eating for 1/2-1hr. on saturdays i usually plan something and dont have muh time so i do 45mins per subject on Sundays and wake up at 9:30. I usually have hw done on friday tho so if you do english or irish, id try to get ur hw done on friday and spend sunday doing the essays.