When I took Evangelism, we learned a format to pray in. Of course you pray however the spirit leads you to... But a lot of people at church did not know how to start or end prayer. Sometimes they didnt know what to pray for... lots of issues, but I think It was in a book entitled Milk of the Word, by Pastor Wilkins out of Texas mentions this way to pray. I think its great.
Acknowledgment
Confession
Thanksgiving
Supplication (I think)