Take the "same" picture each month for the first couple of years. We had our daughter propped up on the couch next to a teddy bear. Stringing the pictures together showed her growth in a beautiful way.

Also, make sure that you don't hold them in order to put them to sleep. Wait until they are relaxed and then put them down in their bed/crib/cot. You want them to be able to put themselves to sleep without you.

Also, don't keep the house quiet when the baby is asleep / going to sleep. This will only condition them to be able to only sleep in the quiet.