What it takes to focus

I am having a slight headache and feeling really sleepy. I couldn't concentrate properly in my German class as well. And why? Because I didnt sleep early last night inspite of knowing that I would probably be in this state if I didnt do so. I was watching this wonderful movie - The Guardian. It was too good to miss.. But actually if I think , life has always been like that. There is always something which is not in my scheme of plans but it appears too good to resist. How do I focus? How do I tell myself that I have to sacrifice something to achieve something bigger in life. I feel the ability to focus is what differentiates the highly successful people from the rest. My experience tells me that it is not enough if I am just talented. I need to have the focus to give my 100% at things which I am supposed to do. I need to realise that this is the first step towards fully utilizing my potential and perhaps figuring out my goal in life. I need to have shot term plans - say a one week plan and I should stick to it no matter what. I need to be able to say no to any kind of distraction. This experiment of focusing on my day to day life may not show instant results but eventually it will affect my life as a whole positively.