Keep a diary every day in English may enhance my English proficiency?

Yet I have just listened the StudioClassroom. I am a little tired now, but actually not sleepy. I'm a little anxious about the coming GEPT HIGH-INTERMEDIATE LEVEL test, administered this Saturday and including parts of speaking and writing, which I worried most. As a result, I make up my mind to compose a short essay a day to sharpen up my writing skills.