Learn how to write an employee appreciation letter with these templates and examples. Download the template for free (PDF or Word).In this article, we explain what an appreciation letter is and how to write one with tips, examples and seven easy steps to write your own. Read on for some starter messages for thanking your boss for support. Here are tips on how to write a letter of appreciation, examples to review, and a template to download to get your own letter or email started. Thank you for being an incredible mentor. Your advice and insights have been instrumental in my personal and career growth. I want to convey my heartfelt gratitude to all the members of the foundation who work tirelessly to make the world a better place for individuals like me. Acknowledge past achievements and express confidence in the employee's future contributions. In the first sentence, say you're grateful for the employee's amazing work.