State who you are, the name of your company or organization, and your position or role. Remind the reader of your relationship to him/her, if necessary.
Use clear, specific language to request the endorsement (clearly describe what it is that you would like endorsed).
Explain why you are requesting the endorsement, what it will be used for, why you feel that the endorsement is necessary or why you merit receiving the endorsement, and so forth.
Include guidelines for the format, length, or content of the endorsement letter. Also, indicate anything else that the reader needs to do to provide the endorsement, such as filling out attached forms and the like.
Indicate by when you need the letter of endorsement.
Consider providing a preaddressed, stamped envelope with your request letter if the endorsement letter is to be mailed.
If you plan to make a follow-up call to the reader, indicate in your letter when you intend to do so.
Thank the reader for considering the endorsement.
Give an Endorsement
Indicate what or who it is that you are endorsing.
Substantiate (or give reasons for) your endorsement.
If you are endorsing a person for a particular position, role, job, etc., include how long you have known the person, in what capacity, the positive qualities of the person that make him/her a suitable candidate for endorsement (including accomplishments and abilities), etc. Be as specific as possible.
If necessary, indicate the next step that should be taken or what will happen next. Include a time frame, if appropriate.
You may want to include your contact information and offer to give further information upon request.
Conclude your letter by summarizing the reasons for the endorsement and by restating your endorsement of the person or project, etc.