would go an hour on, break for some time, do a farm run manually; a little bit of slayer manually, then back to botting, find a pattern that works for you and that can fit in your timeline.
As for what certain day to bot, man that's all superstition and borderline "Anti ban in scripts" fuckery.
also depends on your zulrah run time can you get a kill under 1:30? 1 hour that's significant progress.
It's all an personal decision.
It sounds cliche, but the truth never lies. Just like the old "calories in, calories out for weight loss" it sucks, but it's just thermodynamics