There are many guides available to help you with essay-writing. However, I am mainly familiar with those in English.
- One of my favourites is the long-established students' guide published by the UK's Open University,
- The University of East Anglia has an excellent reputation for teaching how to write well. They have a free, online guide that you can download. It is basic, but you may find it useful. Free, online PDF.
- The University of Southampton has a Study Skills Handbook by Barbara Allan that addresses essay-writing in chapter 7. Chapter 13 on Reflection is unusual and rather good, I think. Free online PDF.
- The Modern Humanities Research Association puts out an excellent booklet on writing: The MHRA Style Guide. You can buy it in print (cheap at $19), or download their free PDF version. Be aware, though, that unlike the other guides above, the MHRA guide is only about the mechanics of writing, spelling, punctuation, footnotes, and bibliographies. It does not help with how to assemble your ideas, or plan an essay. But since it's free as a PDF, it's still worth getting, and will help you answer questions about silly details like what English words should have capital letters, or how to put together your bibliography.
Many guides to writing suggest that you should begin by having a question, and then doing some research, organising your notes, and then writing your essay. Or some variant of this procedure.
I am not sure I agree. I think it's important to start with a question, yes. But sometimes the best way to begin can be to actually sit down and start writing or typing. Write a sentence, or two, or a paragraph, about the question. Then you will begin to feel how much you know and can say, and how much you need to go and read in order to be able to write the next sentence.
The great cultural historian Peter Burke makes some very interesting remarks about his own process of thinking and writing in this 2004 interview (from 3min 11sec). He goes to his desk in the morning and writes. No preliminary reading. Then, in the afternoon, he goes to the library. Writing precedes reading.
Two more late additions. These can be bought second-hand in the UK from Amazon for 0.01p, plus postage!