How do i tell him that i dont want to hang out because I DONT LIKE HIM!?

geez!!! this boy is soo freaking annoying gosh! he wants me to hang out with him and stuff and he asked me out like a 1,000 times! i dont like him! at all! he is UGLY! he keeps complementing me and stuff and i tell him that im not interested and i just dont want nothing to do with him! how can i get him to UNDERSTAND this!!!!!! my cousin tells me to just be blunt and tell him that i think he is ugly, but that is mean also. omg help me