How do I tell this amazing guy how I feel about him?

Asked by Emililly (56) November 1st, 2010 from iPhone

I have known him for about 2 years, I am best best friends with his sister who is my age(she knows I like him and is fine with it) and he’s 1 year younger than me age-wise, but 2 years behind me in school. I am crazy about this guy and I love absolutely everything about him, but he makes me so nervous and gives me butterflies plus I’m a pretty shy person and I’m not sure how to tell him I like him. I wanna ask him to prom too! I feel comfortable around him, just not comfortable enough to come right out and say ‘I really like you!’ I need help please!!!! :)