When you choose the right blanket for your baby, choose something that won't create discomfort for the baby. Breathable blankets are needed for the baby to breath freely. Non-breathable blankets are not a choice since it traps the moisture and brings discomfort to your baby. Breathable blankets allow the moisture to escape and leave the baby's skin dry.
You have to put the allergies to certain materials into consideration. Some babies have sensitive skin and sometimes are prone to allergies. Try to consult your doctor first to make sure what type of cloths doesn't give babies allergies. Do some investigations if your baby has an allergic reaction to a blanket.
You will know for sure if the blanket you gave your baby would be perfect if he or she enjoys being with it and is comfortable with it. You will be able to know if he really is comfortable with it if you can see that he or she sleeps soundly with it. You will not have problems with the baby during his sleep when the baby is already comfortable and loves the blanket dearly.