Revising and Excuses

I'm not great at revising. If anything I'm really quite bad at it. Focusing on one thing and trying to remember it, there's just something in my head that thinks of that and goes "NOOO! NO! No, I refuse to focus. Look, a pigeon! Ooh, isn't that pencil interesting. Oh! Think how many things you could do with those post-it notes!" or "Yeah, I'll revise in a minute, after I read this," and I never do get any revision done. Then I get to school, get into the exam and think "hmm, I'm pretty sure the answer isn't  pencil, post-it note or pigeon."
Of course I can make excuses but they never work when somebody asks and they certainly won't get you through an exam.