Establishing a clear bedtime routine may help when your baby's sleeping schedule (usually around 3-4 months old) become more predictable.
What my friends did was to have a night feed 30-40 mins before bedtime. Following by a bedtime routine of simple wipedown, brushing of teeth/gum, changing into pajamas, bedtime story/lullaby or a "chat" (more like monologue) with baby, patting baby to change the association from being carried to these actions.
For naps, they try to put baby back into cot once baby seemed drowsy enough, but not quite asleep yet.
Sounds simple in theory but most took awhile to make these associations.
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