The Do-This-Massive-Bit Homework dump

Right. Something I have noticed about the difference between GCSE, and AS levels is that the homework is given in a different way. Don't get me wrong, I expected this...

But I was wondering how to deal with breaking down massive homeworks into reasonable chunks with a time scale. For example, just today a teacher said 'finish off this chapter, and make notes, and refer to [this other book], and include that in your notes.'

Now, this an't neccessarily be completed in just one night. So do I split it by covering X amount of pages per night, or by doing X minutes/hours on it per night?

I know a lot of this is dependant on what the task is, but I want general advice. What are the first few things that I should think when I get given a massive task due for Friday?

Thanks for your help...