The best way to do that is to involve them. Just like with anything else, they may pray very simply. But, that can be very effective. The Spirit is given to teach us how to pray, and sometimes He can lead in incredible ways.
For instance, there was a family with several children, who prayed every evening before bedtime. The mother was pregnant, and the smallest girl prayed every night for the baby to be healthy. The couple didn’t think that was needed, because the doctors had found nothing wrong. But, they let her pray for that, anyway. When the time came for the mother to give birth, however, there were sudden complications that nobody expected. The baby was eventually delivered safely, and was healthy. However, that was because they had prayed. God knew what would happen, when they didn’t.
