When you study for the exam, concentrate on central concepts and ideas, and on issues you think might be useful to know in later working life. Search the web for any (central) concepts you do not understand.
The exam may have different types of tasks and questions. For example, the questions may require essay style answers or you may be asked to define and explain some key terms and concepts related to intercultural communication.
The grammar and spelling of your responses will not be graded, as the focus is on content. However, try to make your point as clear as possible, consider your reader and plan your answers to make them coherent. These factors will affect the grading.
If you feel you would like to refresh your essay writing skills, you could check this Purdue University website: http://owl.english.purdue.edu/owl/resource/737/1/
Please note: you are not allowed to use a dictionary or any other materials in the exam.