A nighttime bedtime routine can lead to better-rested children and happier parents (we're pretty sure those two results are related). The idea is that for the 30 minutes before you want her to go to sleep, you follow the exact same rituals in the exact same order: washing up, brushing teeth, book, whatever makes the most sense for you.
There are two keys to implementing it: The first is to start by working around the time when your toddler usually falls asleep. If you don't care for it and want to change it, wait a few days, then adjust it gradually — by increments of around 10 minutes. And the other is to give her notice that those 30 minutes of bedtime rituals are about to begin so she can get used to the idea: "We’re going to get ready for bed in 30 minutes," followed by "We’re going to get ready for bed in 20 minutes," and so on.