I used pretty much the same format for a revision timetable throughout my gcse years (ended up with 999999888A in academic subjects).
What i used to do was to print out a month on the calendar and then write in any tests/mocks/exams i had (as and when i knew when they were) and then id write 0-3 subjects on each day. I would then (for each subject) revise for anywhere between 30 minutes and an hour (to prevent losing focus) when i had that subject written down for the day.
I mostly used this when i had mocks or real exams and found that what worked best for me was to do a science, some maths and one other subject per day Monday through Saturday and then nothing on Sunday. It worked well for me but obviously everyone is different! Also its useful in advance to plan out what you’ll be doing so having a checklist can be really helpful.
Hope this helps and happy to answer any more questions or clarify anything. Best of luck with your studies and i hope you have a lovely day 🙂