Praying in the Sand

When I first heard of this way of praying, the thing that popped into my mind is the song by Michael Card called "Scribbling in the Sand". It is his song about the story in John 8:1-11 where a woman found in adultery is brought to Jesus by the authorities who hope to entrap him. Instead of responding, "Jesus bent down and wrote with his finger on the ground." As Card's song says, "The same finger of the strong hand that had written ten commands for now was simply scribbling in the sand." We don't know what Jesus wrote or if he just doodled in the sand at his feet. We do know that the accusers left and Jesus tells the woman, "go and do not sin again." 

The prayer exercise of praying in the sand, gives God the opportunity to do what Card suggests: "Could that same finger come and trace my souls sacred sand and make some unexpected space where I could understand that my own condemnation pierced and broke that gentle hand that scratched the words I'll never know written in the sand." You can hear the whole song here.
For praying with sand, you simply need a pan of soft sand-you don't want to run into a goat-head while praying! 
Offer the time and yourself to God's hand, using Card's words or your own prayer. Write your 'sin' in the sand with your finger as a way to acknowledge it to yourself and confess it to God. Ask for forgiveness and imagine Christ's hand wiping out the sin as you dust your hand across the words so that they are erased. 
You can write a prayer request in the sand and offer it to God. Then lift it up to God allowing the sand to trickle through your fingers.
Draw your own doodles in the sand as you pray. Let your finger(s) simply move through the sand and concentrate on the feel of the sand on your fingers while relaxing into God's presence.