CVTips.com notes that there are many things to mention in a letter of notice, including short sentences about how good the job was, how the individual regrets having to leave and the desire to use the employer as a reference in the future. These notices should be written as simple sentences, and the overall letter of notice should not exceed one paragraph.
The employee should make sure the letter is written in a courteous manner. To do this, the employee should not write a specific reason for departure in the letter unless the employer has specifically asked for one, because writing detailed justifications for quitting may leave the impression of an ungrateful former employee. Along with this, the letter should not blame any specific individuals for the departure of the employee, as it no longer matters for the job and may cause trouble for the company. The letter should end on a positive note, with the employee hoping to have contributed to the company's productivity and simultaneously asking if the company can be used as a reference. Similar to other courtesies, this makes the employer likelier to agree to write recommendations in the future.
Letters of notice are sometimes called "two-week notices," because two weeks is often considered the minimum amount of time an employee should continue working at the job after the notice is given. This is a courtesy to the employer that positively impacts her willingness to write letters of reference for the former employee.