Start with a fresh mind. Don't write the letter if you have other things on your mind. It can affect what and how you write. Type out the letter. Avoid handwritten letters. It creates a better impression. Use the full name of the candidate, at least at the first instance in the letter. Avoid extremely flowery language. It doesn't make for good letter etiquette. The language should be complimenting, but only to a certain extent. Unnecessary adulation may raise suspicion. If no special format or paper is mentioned and if you are writing as a member of a corporate entity, you can use the letterhead of your firm. It's important that you know or at least get to know the student who's applying for the scholarship. This way, you will be sure of what positive personality traits you can highlight in the letter. Verify all the educational qualifications and other achievements mentioned by the candidate in his/her resumé. As a person writing the recommendation letter, this is your moral duty. Get your hands on the candidate's projects or any assignments that the candidate has submitted in the course of his previous academic course/s so that you can write about them accordingly. Format
Use the appropriate salutation while beginning the letter. If the letter has to be addressed to a particular person, then a simple "Dear Mr./Ms._______," will do. Otherwise, it's safe to simply say "To Whomsoever It May Concern".
This is the first and most important part of writing a letter of recommendation. It establishes your connection with the candidate. Basically, it covers the following points: How you know the candidate.
Since how long you know the candidate.
How well acquainted you are with the candidate.
How and why you are qualified to write the letter of recommendation. This is the most important paragraph, as it is by reading this that the person in charge will decide whether to go...