Prayer is just talking with our Heavenly Father.  Sometimes it is hard to start the conversation.  What do I say?  I say, just what is on your heart.  In the beginning we are like toddlers and just know how to ask for things.  He is just looked at as our source or supply.  As the relationship grows then the dynamics of our relationship changes.  It goes from just wanting stuff to wanting more of the Person.  The disciples had watched Jesus pray, and He prayed differently than the religious leaders.  Their prayers were based on performance and His was based on relationship.