How do you let a guy know that you like him?

I've been thinking of telling this guy I like him for a few days, but I just can't figure out the right way. I want to tell him asap. I'd thought about txting him, but I thought it'd be better to tell him to his face. But I don't know what I should say. Should I just be direct and tell him, "I like you."? Do guys like that or does it scare them?
How do you let a guy know that you like him?
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