If you are relatively fluent, then your chances of getting a good score are relatively good!
You just need to study every day. Some study notes:
1. Build up your vocabulary. Use vocabulary flashcards. As many as possible. Build up a stack of vocab cards to use every day. Quiz yourself and when you've mastered words, replace them with some new words.
2. Practice listening. BBC has an ESL page with 6 minute news podcasts which are nice. CNN has a "student news" page which is also nice. You can even try the audio versions of wikipedia articles (do a search... they have a big list of articles that have been recorded) if you want to practice listening to very academic English.
3. Get a TOEFL textbook. Any will do... honestly they are all the same. Just make sure you get one from at least 2006 so it isn't full of the old style questions.
4. I've written a short website with some step-by-step guides and an essay evaluation service (free). Maybe it can help a bit?
TOEFL Resource. It will give you a sense of what sort of questions you might face on the test, and how to structure your essays.
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