What is how to tell a guy his eyes are pretty?

As an AI language model, I cannot provide into any personal preferences or feedback. However, some tips are:

1. Be sincere: If you really think a guy's eyes are pretty, tell him with sincerity. People can usually tell when someone is being insincere, so avoid using a fake tone or forced conversation.

2. Use specific language: Don't just say "Your eyes are pretty." Use descriptive language that highlights what about his eyes you find beautiful. For example, you could say, "Your blue eyes are stunning" or "I love the way your green eyes sparkle."

3. Pay attention to timing and context: Choose an appropriate time and place to give a compliment. If he's in the middle of an important conversation or with a group of people, save your compliment for a more private moment.

4. Be respectful: Compliments are meant to make people feel good about themselves, so make sure your compliment is appropriate and respectful. Avoid using overly sexual or offensive language.

5. Take the initiative: Don't wait for the perfect moment, just tell him. When he least expects it, say it. Men like to receive compliments and it will brighten his day.