It’s okay if you’re not ready. You aren’t missing out on sleep training if you skip it at 4 months: You truly can start sleep training at any age, even in the toddler years, although experts say it’s smart to be aware of developmental milestones and adjust baby’s sleep schedule accordingly. For example, the week baby learns to walk may be tough to implement a sleep-training schedule, and even a sleep-trained baby may see a regression simply because he’s going through such a developmental shift.
• Have a solid bedtime routine. Experts say that regardless of which sleep-training method you use, having a stable bedtime—between 5:30 and 7:30 p.m. for infants, Vance suggests—and a steady routine are key. Whether it’s bath, book, lullaby, bed or a different sequence, doing the same thing every evening is part of the bedrock of good sleep hygiene. Blackout curtains and a white noise app may also help.