I find that I'm repeating this advice a lot so I thought I'd make a thread for it. If you find that you can't get very far on an essay try this:
1. Write down everything you can think to write on the topic. Don't worry about sentence structure, grammar, or any sort of structure. Just get all of your ideas on paper the best way you can.
2. Try to work out how to organise what you've said into paragraphs, and work out what your contention will be (notice that you work out your contention AFTER you've brainstormed ideas.)
3. If you don't think you have enough ideas, go over all of your notes\readings\textbook\text again.
4. Start writing the paragraph you feel most comfortable writing. If you come to a point in that paragraph where you're stuck, start on another paragraph. Just write whatever you're more comfortable writing
5. Now just put it all together.
This might not work for everyone, but I don't know anyone that it hasn't worked for, if only a little bit.