Dear Pat,
I am sorry for disturbing you for your revision. I saw you looking at your History textbook after the exam had started. As your friend, I want you to get better marks also, but not in this illegal way. If you had revised well, you would not have used this method in the exam.
I think you need to try to be honest. Honesty is very important in your life so you should tell Mr. Wong that you had cheated in the exam to show your regret. You should know why honesty is important. If you are not honest, besides school, the boss will punish you also. I have stressed the importance of honesty here already. I hope you can improve and correct your mistake. I will support you forever!
You may also try to prepare more before the exam. You will build your confidence if you are revising well. Revision is the most important section to help you get higher marks. If you put more effort in it, you will get a good result. I have mentioned cheating is an illegal way to get good marks. This is also a way of deceiving yourself. Moreover, this shows that you do not have any confidence!
You may feel that I am teasing your mistakes, I am your friend so I will show my support to you! In conclusion, I think you should tell Mr. Wong immediately tomorrow to show that you reflected the wrongdoing already, Mr. Wong will understand you!
Best wishes,
Chris