Learn how to write an employee appreciation letter with these templates and examples. Download the template for free (PDF or Word).Discover 30 creative ways to say "thank you for your support" in this article. Strengthen your relationships and spread gratitude with these unique ideas. Below you will find sample appreciation letters to send or email an individual or individuals who have helped you at work. Guidelines for writing appreciation letters: State what you appreciate and briefly explain why. Below is a comprehensive guide to help you transform a standard thankyou letter into a pivotal moment in creating strong relationships that last. Sending out customer appreciation letters is an excellent way to connect with your clients. Learn how to write a customer appreciation letter here. Here are some components that influence donors to continue supporting you in the future. 1. Timing.