I was an awful procrastinator, and I came up with a method that helps me. I will try to explain how I do it here.
I always find if I know I need to do something by a certain time, vaguely in my subconscious I will picture myself not doing it and the consequences, eg. a person such as DS' teacher, or my college tutor, standing in front of me and thinking or saying that I am hopeless. Now I bring that feeling of dread into my concious mind. I give it form, weight, allow myself to believe it has already happened. I have procrastinated to the point of uselessness yet again.
Next, I picture myself saying to that person, "Ah ha! But I did do xyz, and I fucking aced it, here it is, so put that in your pipe and smoke it!" Or words to that effect.
Now bringing myself back to reality, I imagine that I have used my time travelling device (I use Hermione's time turner, but you can use whichever method of time travel you prefer) to go back from the first reality in order to change the course of time and give myself a second chance to get it right. I stand up at this point and say out loud "Fuck you teacher! I'll show you" or similar. Then I go and do the things I need to do, and don't rest until I know that my "Fuck You!" moment is in the bag.
I hope that helps you ladies, it really helps me, although it is completely bizarre.