When you catch yourself procrastinating you should take a break and ask yourself “What am I avoiding?”. In general you will quickly find the answer (if you did not know right from the beginning). Now you take away all other staff in front of you and think of how you will reward yourself after completion if this thing you are avoiding.
Then you start working on the most difficult or unpleasant part of this task. Once you overcame it the rest will go very smoothly and at the end you can enjoy your reward.