At first your baby will just lie there (and may even start crying). But tummy time is important for developing the muscles that your baby will use to roll over, sit up, and crawl. Make it fun and safe by staying close and offering encouragement. Lie down next to your baby and try putting your face in front of your baby's. You can also roll up a towel or blanket and put it under your baby's chest to give your baby a better view.