I truly started implementing it when they were 3 months old. My philosophy is 0-3 months you do what you gotta do to survive. 3-6 months start establishing a routine that works for your family. 6 months, fully enforced routine and operation ditch the soothers
day 1 really.... with a lot more flexibility early on- but gradually working right into the rotations throughout the day. I followed Baby Wise, which is essentially the same idea- sleep/eat/play rotations all day long.
Re: When did you start EASY?