After you have written down the date, you can move on to the body paragraph that contains your intention to apply for job. Things you would state include your objective of joining the company? How can you enhance company's productivity? What is your previous experience in the field you are applying for? What is your academic background and how it can help you in your job? Lastly you can list down basic skills and experiences that you have attained from previous jobs, if any.
The lawyers add that: "This is the legal problem with a Letter of Intent _ you can't legally state you agree to something and then state that you don't in the same document." Famous Case of a Letter of Intent Gone Bad: Court Case of GETTY OIL vs. PENNZOIL