My lo doesn’t have any routine before she started school (because I sleep at 7/8am myself 😓). She sleeps at 12/1am (regardless naps or no naps, sometimes she stays awake till 4am doing nothing 😑) till next day 2-3pm and this routine continued all the way till 2.5yo. Surprisingly the day she started school, although she slept late, she was able to wake up at 7am then from then, she sleeps at 8-9pm till next morning (first few days confirm will cry during morning cause haven’t get used to it yet). Of course, I’m not encouraging you to not have a routine, it is still better to set a routine for them to get used to it first before they enter school (and of course it’s better for young kids to sleep early).
If you wanna set a routine, I feel you can try the timetable method but follow the timings strictly especially for naps. Cause our LO’s sleep timings all haywire, you have to let them get used to the routine first.
If you wanna follow the school timing way: wake lo up at 7/7:30am regardless what time they slept last night, then let her have their nap at 12-2pm, keep her awake till 6-7pm then put her to bed. Let her get used to sleeping and waking early then slowly twerk the timings. My lo now wakes up at 8am on weekends 🫠.