Train from the start. Newborns are wired to feed by instinct and drift off when tired (without knowing they are sleeping). Many have success setting a pattern the first days: a two hour nap; wake to feed; body care; followed by play until signs of fatigue begin and baby is placed in their comfort place to sleep.At night they wake on their own to feed but limiting day naps prevents day/night reversal.
Practice. During the first 3 months it is difficult to train your baby to a good nap schedule. They are just feeding too frequently! however after this time you can begin trying to introduce a schedule. Try to stick with similar routines each day. Feed, play with your baby and keep them awake and then go through a bedtime routine, such as singing, turning down the lights and putting them down.