(Almost no applicants do this, or do it effectively) Convey your
interest in the particular organization and position to which you are applying by detailing your knowledge of the company and the industry in which it operates.
Identify the position you are applying for and how you discovered the opening (e.g. in the newspaper, on the company's website, etc.) You may also mention the name of the organization and express the reason for your interest
in that particular organization.
As for the content, you should mention the reference of the advertisement and why you are interested
in that particular organization.
Once you have established that you want to work
in a particular organization, or have narrowed down your search to 2 or 3 restaurants, begin by creating a job application set.