Summarize the following:
All babies are different, and not all like to go to sleep the same way, but most like to be gently rocked. Try holding the baby in your arms and slowly swinging the baby back and forth, or holding the baby securely while walking around with a bouncy step, or rocking in a rocking chair. If the baby won't go to sleep, gently lift the baby up and lay the baby in its crib.  Never leave a baby in its crib on its back with its bottle in its hands because the baby could choke. After the baby is asleep, sit in the baby's room with it and wait to make sure the baby will stay asleep, and that the baby's sleep environment is safe -- Make sure there is nothing that the baby could play within the crib. It could distract the baby and it won't want to go to sleep. Also, soft toys should never be in a crib, because a baby could suffocate. Keep big, fluffy blankets or pillows out of the crib. Babies don't really need them and they are actually dangerous. Keep bed covers away from baby's face.  Do not lie a baby on its tummy, ever, even if the parent tells you too. Always place it on its back. Placing it on its tummy is very dangerous, and potentially fatal. (If the baby is old enough to flip itself over on its tummy by itself, though, it's okay if he flips himself over). Keep checking on the baby as it sleeps. This is very important as it is your babysitting duty to make sure that the baby is safe, is not fussing, is not too hot or cold and does not have a dirty diaper. Baby monitoring is fine if the parents are fine with it, if they don't have a baby monitor, or grant you permission to use them, check on them every 15 minutes.

Summary:
Rock the baby gently. Check on the baby.