What are some Guidelines for Preparing an Effective Letter of Recommendation?

When preparing a letter of recommendation do the following:

• Type the letter using a standard business format.
• Address the letter to "Human Resources construction manager" or
  "Recruiting construction manager."
• Start your letter by explaining your relationship with the construction executive.
  
• Be honest. If you cannot honestly endorse this construction executive, you must decline.
• Review the construction executive's résumé. Talk with him about his accomplishments
  and goals.
• Describe the construction executive and support your description with specific
  examples from your experience with him.
• Choose your words carefully. Instead of using generic adjectives such
  as "excellent," use ones that pinpoint the construction executive's character and skills
• Since you know the construction executive's construction career goals, try to use descriptions that correlate to those goals.