Write one sentence that serves as a clear closing for your letter. For instance, you can say: "I'm glad I finally told you how I feel." Or you can state: "That's everything I wanted to say." If you are not already in a relationship, you should avoid being overly romantic and stick with something simple.
Prompt the guy for a response. Give him your phone number or say, "I'd like to hear how you feel as well." Your crush may like you but have no clue what to do next, so give him some ideas.
End your letter with a simple signature. While you may be tempted to write "Love, Sarah" or "Sincerely, Jane," it is usually best to just sign your name. You can get creative with your signatures when you are both exchanging actual love letters.
Add a brief "P.S." message, if you feel the situation requires it. Thank him for helping you with a recent project or compliment his new glasses. This section is entirely optional.