How do I compliment a guy?

matthew always compliments me, your beautiful, stunning, gorgeous, adorable, damn, hot, breathtaking, you have an indescribable body, and i dont know how to return that. do i say, your hot? or just cute? or what can i say? i dont wanna say the same thing everytime. he has those pale blue eyes that kind of give you the chills and he is kind of short, but super muscular and benches like 240. how do i compliment that? im 15 and hes 17 so age according, not grade school, thanks! :)