Willpower is a finite, exhaustible resource.
Have you ever noticed that you waste a lot more time surfing aimlessly on the internet at night than during the day?
This is a really important topic, since your willpower is the sole most important factor of how productive you are. And yet willpower has a bit of a strange rap about it. People tend to look down on people that admit to having problems with willpower, which is kind of weird (it's not like we look down on people because they are, say, color blind). Further, the way that people think of it is not quite accurate - most people see it as stable and consistent, when in reality your willpower disappears throughout the day (and so is highest immediately in the morning).
The idea is that willpower is like a muscle that you use every time you make a choice, and the muscle can get exhausted and leave you making bad choices. It comes back with sleep, which explains why you seem to waste the most time during the night just before you go to sleep.
Ways to save willpower:
* Remove the choice.
If you find yourself wasting a ton of time on the Internet, you can remove the choice entirely by disconnecting from the Internet. The initial choice to (say) turn off the Internet is hard, but when you keep the Internet off, you will not have to make the choice every 5 minutes to continue working instead of surfing your favorite site.
It's as if turning off the Internet initially takes a lot of willpower, but after that you don't have to expend any, whereas if you keep it on you have to constalty expend willpower to not waste time. After a certain point, you will have saved willpower.
You can really remove the choice by involving someone else ("only let me back on the internet once I finish my essay").
* Make a habit.
This is similar to removing the choice in that once you make a habit out of something, it stops being a choice - you just do it. I used to browse webcomics all the time, but I have since made a habit out of only checking them immediately when I get on the computer the first time of the day. Then I don't waste willpower throughout the day wondering if I should go check xkcd or something.
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