I am gay and in love with this guy. When and How do I tell him?

I think I am gay. I have not had sex before, and have never kissed a guy or a girl before but somehow I enjoy the company of guys, particularly this college mate of mine.

We have spent several holidays away together, sleeping on the same bed but nothing happened, we all just assumed we were straight but sometimes there are ways that he acts that tells me he is gay.

I really love him for the way he is. He is so caring and lovely. He is very nice and always puts my needs first before his. I find this very adorable and have dreamed of kissing him and just romancing. His is just so amazing, amazing is just an understatement.

As of now, we are like close 'brothers' but i want to take the relationship to a new level. However at the same time I am worried I might ruin the relationship and we will not talk forever.

What should I do? I need your advice.