The big ones can be really intimidating, can't they?

But, you know what? If they weren't challenging, you wouldn't be learning anything.

Here's what I do: right at the beginning, I get a couple of pieces of paper out, and some coloured pens/textas.

I write down the assignment question. I then divide it into chunks, by underlining the bits that are the key words. Then I sit and stare at it for about 5 minutes, soaking in what the question is. Then I think about which bits of what they've taught might be the bits that answer those chunks, and I jot those down, kind of like a free-form mind map. Then, I get another piece of paper and turn the question into a set of headings. Under each heading I jot down a few ideas, keywords, plans of what I need to do/find/write about.

This process gives you a set of really clear, small steps you can follow, instead of one big uber-assignment. If you're still confused/uncertain at this point, contact your tutor/lecturer, or a study buddy, and sound out your ideas. They will soon tell you if you're on the right track or not.