How do you get friendly with a cockatiel?

I have a male cockatiel and apparently he was hand-fed. But for some reason I think he's scared of me. Whenever I put my hand in the cage, he hisses and tries to bite. He keeps looking at the little mirror in his cage and doesn't pay attention to really anything else. I think he thinks that the mirror is another cockatiel looking back. He occasionally fights with the mirror as well. I try to coax it out of the cage sometimes but it's hard since he won't even come close to my hand. Every time I succeed in getting him out, though, he flies around the house everywhere and wouldn't stop squawking. Please help! I really want to play with him and let him know that I'm no threat.