I didn't read any parenting books before DD was born. IT was just a personal preference. In fact, I don't think I did until she was about 10 months old. It was based on a bit of surfing I did on parenting issues while pg. I came across something on an 'issue', I can't remember what, on a parenting website and the articlse started, 'There are two arguments on ...' and I just thought: I don;t want to listen to anyone else's 'arguments' before I've even met DD. I just want to get to know her. Although I wouldn't do everything exactly the same as the first time round, I'm glad I made that decision.
I found DD fell in and out of routines throughout babyhood. It was nice when we got into one rhythm and confusing when it changed but up to a point it was good to follow her. As soon as we got into one, however, another one started pretty soon. She is routinised now, but only because she likes it (she's 2.2 - and I did choose the routing but only persisted because it worked for us both).
In terms of imposing one on them, IME people who tried to very early on really didn't enjoy early baby days as the baby would not conform! They start to remember things other than your face, you nipple etc around four months. Before that, I think (personal viewpoint warning!) that you might be beating yourself up over nothing trying to get into one.
I do know one or two parents who got into a routine very early and it made them feel more in control. I know mopre parents who burnt their parenting books in the back garden a couple of months in. For the ones who got into a routine early, it did seem to have involved leaving the baby to cry a lot. I suppose it depends if you're ok with this or not. Personally, not my cup of tea - at least when they're so small.
On a different note, was surprised and pleased to realise milk (or rather colostrum) has arrived already! I must have been inspired by bf counselling training on Saturday. We were doing a session on helping mothers with attachment and positioning using weighted dolls and it was rather realistic and I couldn't wait to get going again. Clearly, my body has taken the cue!