Your baby will sleep and wake according to her needs and feelings. Some babies wake almost only to nurse. Others are awake longer from their first days out of the womb. The amount of time they stay awake will be longer as the weeks pass.
As with adults, newborn babies go through different sleep cycles: drowsiness (light wakefulness), calm sleep and agitated sleep. When your baby is in her agitated sleep cycle, she may make sucking movements, frown, cry, smile, jump, tremble, groan, breathe hard or move. This is normal. No need to wake and comfort her. However, you may want to wake her if she needs to be encouraged to feed.