7. Does your DS sleep in the same room or separate? Once you put him down in his cot, stay in the room and quietly fuss about a little bit. That way he knows you are still around and if he does tend to wake up quickly again, he will see you are there and trust more that you are still around when he wakes up again.

This is good advice. I occasionally stay in the nursery with dimmed lights and quietly fold nappies (cloth) or put away clothes (our wardrobes are close by) and sometimes my boys just drifted off through boredom watching me LOL