The primary purpose for Jesus praying was for him to be in contact/communication with the Father.  St. Mark would not need to tell us this with the details he uses if there was not something special that the Holy Spirit wanted us to know.  In all of what Jesus does he is an example for us, teaching us. In this verse, Jesus is teaching us about prayer. There are two key elements in this verse: 1) very early before dawn, 2) off to a deserted place.  By rising very early before dawn, Jesus shows us that our priority needs to be prayer. Next, Jesus demonstrates by his going off to a deserted place, the importance of praying without distractions or interruptions, and with focus and concentration.

Are you looking for help to improve your prayer life? Follow the example of Jesus and do two things: make prayer a priority, and pray in solitude so you can focus.