We introduced our routine around 3 months and it's been great.
Bath (only every 2nd night), creams (eczema baby), nappy change, pj's, grobag, bottle, stories.
We've always done the same 2 stories which we now know by heart (!). As soon as she hears the start of the first one, she gets that it's bed time and time for sleeping. This has worked when she's away from home and even away from us. It's also useful if she wakens at night - we don't use it every time - only if she's really awake in the middle of the night for some reason. It generally settles her nicely.
We use Each Peach Pear Plum and Goodnight Moon.