Most parents are worried that their baby is too cold. It is more likely however that your baby will be too warm than not warm enough. Do not over clothe the baby or use heavy blankets because he or she will be uncomfortable. The clothing that you choose will be highly individualized based on the time of year that your child is born. If it is a warm day and you are comfortable in a t-shirt and shorts a diaper and a onesie should be adequate for the baby. If you are chilly and need a sweater the baby may need more clothes and socks and a hat too. Basically your baby should be wearing the same number of layers as you are.