IELTS candidates should try to learn at least a word a day and this habit should be started as long before the actual IELTS exam as possible. It’s no good trying to learn new vocabulary the day before the exam. That’s too late. It really is. A good IELTS student notes down new vocabulary learned and can find the vocabulary again. A good IELTS student learns the different forms of a new word eg the past simple form of a new verb and also learns the pronunciation. Don’t leave learning new vocabualry too late.