18 month sleep advice

Can anyone give me some advice on what I need to do to help my 18 month old kid fall asleep more peacefully/independently?

Right now, we have a whole bedtime routine but it involves me rocking her to sleep which is no longer working. She sleeps through the night but it takes like at least an hour to get her to sleep and were about to have another kid in a few months so that’s not going to work. She used to fall asleep fast being rocked to sleep but now it’s like she’s uncomfortable in my arms. She tosses and turns and fusses the whole time until she finally passes out. We pay close attention to her awake windows and sleep cues so I know she’s tired when we’re going to start her routine. She’s not ready for a big kid bed where I could lay with her or help her get more comfy in bed so I’m not sure what I should do. I need a way for her to go down to bed more easily.