What I learned from my 1st pregnancy is that I worried too much about the pregnancy research and didn't do enough research on the actual birth (like how to deal with labor pains) and I didn't do enough research about what to do once baby got here.
With the labor, I thought since I was being induced and getting an epidural, I wouldn't feel any pain......huh, huh. Oh there was pain alright. I wish I would have read and practiced what to do to help deal with contraction pain.
Also, once baby got here, I finally got around to reading that Baby Whisperer book. Yeah, I should have read that thing BEFORE baby arrived. I wish I would have had a plan and gotten professional advice (by reading) before those first few days instead of waiting until I had done the wrong things for weeks.
And ultimately, I learned that you just do what you have to do to survive and try to stick to the original plan as much as possible but really anything you do during the first couple of months can be undone. Babies are very adaptable before a certain age so just do what you can to survive the first couple of months, then focus on getting into a routine and being more strict about sleep.
OH AND, do your research on SIDS before baby comes home. Most of it is common sense but there are a few risk factors that may not be common knowledge to you. I would have GONE INSANE without my Angelcare monitor. We still use it with DD#1 and she just turned 1yr old.