Good vocabulary for an essay, get more help with ielts preparation on the main pages of my site
Then try these homophone games.
Another good idea is to keep a word journal. If you think about it, there are opportunities all around you to develop this important skill, so spend time every day reading and listening to take in new words and then develop a system to incorporate these new words in your writing and speech.
Be sure to pay attention to vocabulary words as you read. Although the vocabulary errors occur quite often and are not easy to spot, being aware of them will definitely help you improve your writing.
Write down the sentences that you hear. Try to find a self-paced course that uses assignments and quizzes to hep you increase fluency and brush up on your writing skills.
Listen for them in the world around you.