Writing a Formal Letter of Request has the following format-
First, on the left side of the page write the date on which you would write the letter.
Then, write the full name and address of the person to whom you are writing the letter.Come down a little and on the right hand side write your complete name and personal details.
Start your letter with a salutation like Dear Sir/Madam,
The main body of the letter is divided into 3 parts or paragraphs. The first is the introduction to the letter, the second paragraph is related to the main topic of the letter and the last paragraph would be the concluding paragraph.
At the end, finish your letter by writing Yours Faithfully followed by your name. This would be on the lest side as well.
Hope it helps!