Hi,
I would read this article, and pay close attention to #2 about how to tell if baby is completely asleep:
8 INFANT SLEEP FACTS EVERY PARENT SHOULD KNOW
We've been fooled many a time, including this very minute when my DH thought my son was asleep just now, and yet the second he put him down, he jumped right back up, and now here he is in my arms... in this case, I believe Dr. Sears says to try again, and then wait even 20 minutes after you think that baby is asleep... then try the limp limb method again... our older son was a very light sleeper and it took him a LOT of time to get into the second stage of sleep where it was okay to try to put him down.
Plus, look in NCSS about how to gently put baby down... she has about a page on how to make sure you are really putting baby down with little to no disturbances... it's hard to do with a crib... but still it is a huge change in a baby's body to go from cuddling on a shoulder to be put down on their back... their whole center of gravity moves and it can wake them up and even startle them unless it is done slowly slowly slowly, with gentle rocking, then making sure you don't let go when the are finally down on the crib, you are still holding them with your body close as it was when you had them nestled up to you... and then slowly you can lift yourself away... this is the way to not wake them from this cozy slumber...
I can't remember what page it's on... I lent the book to a friend... in any case, it's in there and it's quite detailed.
Hope this helps
