Open with a short, but enthusiastic, bit of praise. Let the company know right off the bat that you believe in this person. You don’t have to be over the top or insincere, but a positive note to start will make a big difference. It makes me extremely happy to recommend Michael for the position of Director of Development at XYX Corporation. Any company should count themselves lucky to have an employee as bright, friendly, and dedicated as Gina. No matter what she does, Helena Bonham does it well.
Get feedback. If you’re not sure of your letter-writing skills, or if your letter will carry a great deal of weight for the candidate’s application, ask for feedback from a trusted colleague who may also know the candidate. If you are putting your reputation on the line for this person, you want to put your best foot forward with this letter.