Does she go to bed at the same time every night and get up at the same time every morning? If so you have a routine.
We found the latter a game changer. She has a gro glow clock in her room and we have the phrase one the morning when your clock turns yellow with the sun' and I do an alarm on my phone for when she's in with me.
We'd go out somewhere in the morning (Park, shopping when the weather was bad, swimming, play group, the weekly shop) so she'd burn off energy and then drive around til she fell asleep on the way home. When we got home, I'd carry her in and she'd nap on me. Being in a car seat is like having a big hug and movement is soothing, that's why most kids fall asleep in the car. I say most because some adopted/fostered children find car journeys too traumatising.
The other thing I found when it came to sleep is that every so often I'd have to increase the amount of exercise she had in a day. Getting an indoor trampoline helped with this though.
Don't worry about getting her into a routine for nursery, etc, if she goes, that'll be their job.
We stopped day time naps when she either didn't fall asleep in the car or woke up when I picked her up once home on a regular basis. The only unexpected issue we had when she dropped the day time nap is that she went from sleeping through in her own room to coming in with me virtually every night to recreate that physical closeness.