i didn't set the sleeping time for the maid... i only set the duties from 7pm...(e.g. dish washing... clean up kitchen, take the rubbish out..etc) so, if she complete early, she can go to sleep early lor... as long as she complete the tasks assigned.
you can set different 家務 daily... some are must do daily, some can be done once or twice a week...
and on weekends, i usually assign those need to be done once a week... And now my babies are older, i need to take them to playgroups... i usually will give her a timetable in the morning...
try to make yourself flexible... and most importantly, the schedule should be fit into your daily life.... she is here to help, not to add trouble.